Does bariatric surgery change pregnancy outcomes?

2018/2019 Cátia Filipa Pinheiro Ramos A cirurgia bariátrica altera os desfechos da gravidez? Does bariatric surgery change pregnancy outcomes? março, 2019 Mestrado Integrado em Medicina Área: Ciências Médicas e da Saúde - Medicina Clínica Tipologia: Dissertação Trabalho efetuado sob a Orientação de: Doutor Silvestre Carneiro E sob a Coorientação de: Doutora Alexandra Matias Trabalho organizado de acordo com as normas da revista: Obstetrics & Gynecology Cátia Filipa Pinheiro Ramos A cirurgia bariátrica altera os desfechos da gravidez? Does bariatric surgery change pregnancy outcomes? março, 2019 Dedicatória À minha Mãe e ao meu Pai, por me apoiarem e me possibilitarem realizar o sonho de ser médica, por não me deixarem desistir quando tudo parecia impossível, por serem os melhores pais que poderia ter. Muito Obrigado. Amo-vos Pais. À minha Avó e ao meu Avô, por sempre acreditarem que seria capaz, por me ouvirem a desabafar, pelo carinho e o colo que só eles me sabem dar. Muito Obrigado. Amo-vos Avós. Ao Mário, por desvendar todos os mistérios informáticos que os meus computadores teimam em fazer aparecer, por trazer polémica e humor às nossas conversas. Obrigado Amigo. Ao António, por ser como um irmão para mim, por me instigar a dar sempre o meu melhor, por poder confiar cegamente. Obrigado Tony. Ao Campeão, por ser o melhor e mais silencioso companheiro de casa, pelas horas que me ouvia a recitar matéria, pelos passeios inesquecíveis. Muito Obrigado. Amo-te Pia. Ao Daniel, por ser quem me acompanhou nesta jornada que foi medicina desde o 1º dia, por suportar as minhas frustrações, desilusões e mágoas, por ouvir horas e horas de reclamações e choros, por nunca me deixar cair. Muito Obrigado. Amo-te Barbosa. Assim comecei o meu percurso em Medicina. Assim continuo o meu percurso em Medicina. “Cântico Negro” “Vem por aqui”- dizem-me alguns com olhos doces, Estendendo-me os braços, e seguros De que seria bom que eu os ouvisse Quando me dizem: “vem por aqui”! Eu olho-os com olhos lassos, (Há, nos meus olhos, ironias e cansaços) E cruzo os braços, E nunca vou por ali… A minha glória é esta: Criar desumanidade! Não acompanhar ninguém. —Que eu vivo com o mesmo sem-vontade Com que rasguei o ventre a minha Mãe. Não, não vou por aí! Só vou por onde Me levam meus próprios passos… Se ao que busco saber nenhum de vós responde, Por que me repetis: “vem por aqui”? Prefiro escorregar nos becos lamacentos, Redemoinhar aos ventos, Como farrapos, arrastar os pés sangrentos, a ir por aí… Se vim ao mundo, foi Só para desflorar florestas virgens, E desenhar meus próprios pés na areia inexplorada! O mais que faço não vale nada. Como, pois, sereis vós Que me dareis impulsos, ferramentas, e coragem Para eu derrubar os meus obstáculos?… Corre, nas vossas veias, sangue velho dos avós, E vós amais o que é fácil! Eu amo o Longe e a Miragem, Amo os abismos, as torrentes, os desertos… Ide! tendes estradas, Tendes jardins, tendes canteiros, Tendes pátrias, tendes tetos, E tendes regras, e tratados, e filósofos, e sábios. Eu tenho a minha Loucura! Levanto-a, como um facho, a arder na noite escura, E sinto espuma, e sangue, e cânticos nos lábios… Deus e o Diabo é que me guiam, mais ninguém. Todos tiveram pai, todos tiveram mãe; Mas eu, que nunca principio nem acabo, Nasci do amor que há entre Deus e o Diabo. Ah, que ninguém me dê piedosas intenções! Ninguém me peça definições! Ninguém me diga: “vem por aqui”! A minha vida é um vendaval que se soltou. É uma onda que se alevantou. É um átomo a mais que se animou… Não sei por onde vou, Não sei para onde vou —Sei que não vou por aí! José Régio, in 'Poemas de Deus e do Diabo' 1 Does bariatric surgery change pregnancy outcomes? Cátia Pinheiro-Ramos, MS1,2; Bruno M. P. M. Oliveira, PhD3,4; Tiago Aguiar, MD2; A. Matias, MD, PhD1,2; Silvestre Carneiro, MD, PhD1,2 1Faculdade de Medicina da Universidade do Porto (FMUP); 2Centro Hospitalar Universitário de São João (CHUSJ), Porto, Portugal 3Faculdade de Ciências da Nutrição e Alimentação da Universidade do Porto (FCNAUP); 4LIAAD – INESC TEC, Porto, Portugal ABSTRACT OBJECTIVE: To evaluate the impact of bariatric surgery on maternal and neonatal outcomes. METHODS: This is an observational and retrospective cohort study. Two main groups were defined. For the study group (Post-BS group), we included women who underwent one or more weight-loss procedures and delivered a child (n=97). Only the first pregnancy after the last bariatric surgery was considered. For the control group, we selected women who had pregnancies but had not been submitted to bariatric surgery – All-Controls (n=9375). We further defined a subset of this group, including women with a pre-pregnancy BMI≥35 kg/m2, named Obese-Controls (n=412). We focused our analyses in gestational diabetes mellitus (GDM), gestational hypertensive disorders (GHD), caesarean-delivery, prematurity, large-for-gestational-age (LGA), small-for-gestational-age (LGA) and congenital malformations. RESULTS: Post-BS women had a higher pre-pregnancy BMI than all-controls and a lower pre-pregnancy BMI than obese-controls. There is a higher prevalence of GDM in the post-BS women when compared to the all-controls (p=0.006) and a lower prevalence when compared to obese-controls (p=0.123). The prevalence of GHD was similar between the post-BS women and all-controls (p=1.000), being lower relative to the obese-controls (p=0.146). Post-BS women had a higher prevalence of caesarean-delivery when compared to all-controls (p=0.175), but a lower prevalence when compared to obese-controls (p=0.358). Post-BS neonates had a higher prevalence of prematurity than neonates of the all-controls (p=0.236) and obese-controls (p=0.551). Post-BS women had a lower prevalence of LGA neonates than all-controls (p=0.376) and obese-controls (p=0.019). Concerning to SGA, post-BS women had small neonates with a higher prevalence than all-controls (p=0.159) and obese-controls (p=0.067). A higher prevalence of congenital malformations was found in post-BS women when compare to all-controls (p=0.003) and obese-controls (p=0.022). CONCLUSION: Bariatric surgery improves some pregnancy outcomes relative to obese women, having less than one-third of the LGA prevalence. However, bariatric surgery worsens other pregnancy outcomes relative to obese women, having more than three times the prevalence of congenital malformations. KEYWORDS: obesity, bariatric surgery, pregnancy, maternal outcomes, neonatal outcomes 8 weight-gain per week (OR=1.468), older age (OR=1.052/year) and smoking habits (OR=1.179). Inversely, the risk of a caesarean-delivery decreased with the number of gestations (OR=0.827) and with shorter gestational times (OR=0.868/week). When analyzing to post-BS and obese-controls, caesarean-delivery risk is augmented with older age (OR=1.082/year) and decreased by RYGB (OR=0.342), number of gestations (OR=0.805) and shorter gestational times (OR=0.826/week) (Tables II,V). Post-BS neonates had a higher prevalence of prematurity than neonates of the all-controls (p=0.236) and obese-controls (p=0.551). Considering prematurity relative to post-BS and all-controls, the risk factors were: a lower weight-gain per week (OR=1.754), a higher maternal age (OR=1.034/year) and smoking habits (OR=1.265) (Tables II,VI). Regarding the obese-controls no significant risk factors were found. Post-BS women had a lower prevalence of LGA neonates than all-controls (p=0.376) and obesecontrols (p= 0.019). The major risk factor for LGA, when studying post-BS and all-controls, was the higher than recommended weight-gain during pregnancy (OR=2.375). Other risk factors for LGA were: longer gestational times (OR=1.442/week), higher pre-pregnancy BMI (OR=1.054/(kg/m2)) and the number of gestations (OR=1.140). Furthermore, smoking habits were negatively related with LGA (OR=0.545). Relative to post-BS and obese-controls, LGA risk is augmented with longer gestational ages (OR=1.405/week) and decreased by bariatric surgery, either restrictive or RYGB (OR=0.276) (Tables II,VII). Concerning SGA, post-BS women had a higher prevalence of small neonates than all-controls (p=0.159) and obese-controls (p= 0.067). Compared post-BS and all-controls, the main risk factor for SGA was BS, mainly RYGB (OR=2.508), followed by smoking habits (OR=2.476). Other risk factors for SGA neonates, in all-controls group, were: below-recommended weight-gain during pregnancy (OR=1.756) and age (OR=1.024/year). On the contrary, protective factors for SGA were: a higher pre-pregnancy BMI (OR=0.960/(kg/m2)), a longer gestational time (OR=0.778/week) and a higher number of gestations (OR=0.890). Regarding to post-BS and obese-controls, the major risk factor for 9 SGA neonates was also RYGB (OR=2.808), followed by smoking habits (OR=2.437). The protective factor was the longer gestational time (OR=0.828/week) (Tables II,VIII). A higher prevalence of congenital malformations was found in post-BS women when compare to allcontrols (p=0.003) and obese-controls (p=0.022). When analyzing post-BS women and all-controls, the main risk factor for malformations was bariatric surgery (p=0.001), with restrictive procedures (OR=5.846) having a higher effect than RYGB (OR=4.295). Considering post-BS women and obesecontrols, congenital malformations were increased by restrictive-procedures (OR=4.564), with RYGB having a no significative effect (p=0.068). Gestational age was negatively related with malformations for both control-groups (OR=0.836/week; OR=0.758/week) (Tables II,IX). DISCUSSION Bariatric surgery improves some pregnancy outcomes relative to obese women, having less than onethird of the LGA prevalence. Furthermore, bariatric surgery also decreases, although no significantly, the likelihood of GDM, GHD and caesarean-delivery. However, bariatric surgery worsens other pregnancy outcomes relative to obese women, having more than three times the prevalence of congenital malformations. Post-BS women also have a higher prevalence of SGA neonates than obese women, although non-significant. In our sample, post-BS women had higher GDM prevalence than all-controls, as in other studies 25,26, and lower prevalence than obese-controls, as reported by other authors 4,27-33. This may be explained by the metabolic effect of RYGB, (the major risk factor), but also by the lower weight-gain during gestation, the higher pre-pregnancy BMI and by older age. It appears that RYGB has implications on glucose metabolism that outweigh high BMI on GDM risk 34. However, after adjusting for pregnancy weight-gain, the prevalence of GDM did not differ between post-BS and obese-controls and prepregnancy BMI was not a significant covariate. Nevertheless, weight-gain during gestation may be affected by RYGB and after the diagnosis of GDM. Apparently, on one hand, bariatric surgery 10 reduces the risk of GDM by helping to achieve a lower pre-pregnancy BMI, but on the other hand surgery may increase GDM risk through lower the weight-gain during gestation. Post-BS women had a similar prevalence of GHD compared to all-controls and a lower prevalence of GHD compared to obese-controls, as in other studies 4,28,31,33-35. Since post-BS women had lower pre-pregnancy BMI than obese women, they had lower GHD risk from BMI 27. Regarding the deleterious effects, a weigh-gain above-recommendations may have a negative impact on GHD outcome, mostly for women with a higher BMI at the beginning of pregnancy. Therefore, bariatric surgery may reduce the prevalence of GHD by the weight-loss effect but may have a negative impact by delaying childbearing age. The higher prevalence of C-sections in post-BS women related to all-controls, as reported in the literature 25,28,36,37 and confirmed in our series, may be due to restrictive procedures, namely AGB and SG, which are risk factors for caesarean-delivery, even after we adjusted for pre-pregnancy BMI and weight-gain during pregnancy. We can hypothesize that the higher likelihood of having a C-section on women that had restrictive procedures, when compared with RYGB, is due to a lower weight-loss between surgery and pregnancy. The lower prevalence of C-sections in women that underwent RYGB relative to obese-controls, in line with the literature 28,30,35, is associated to weight-loss after surgery. Higher prevalences of prematurity are found among older mothers and those with lower weekly weight-gain, which may explain it being more common among post-BS mothers than in all-controls, albeit not significantly. The similarities related to prematurity, that we observed between post-BS and obese-controls, can be explained by bariatric surgery not representing a high risk for preterm-delivery in obese mothers, as reported by other authors 4,36,38,39. A higher probability of LGA neonates is related with gaining weight above-recommendation, a higher pre-pregnancy BMI, a larger gestational age and a higher number of gestations. Relative to obesecontrols, the lower prevalence of LGA neonates among post-BS women, as in other studies 4,28,31,34,4043, may be related to lower pre-pregnancy BMI achieved through bariatric surgery. 11 Women that underwent RYGB had a higher prevalence of SGA neonates than both control-groups, with restrictive-procedures (AGB, SG) having a similar SGA likelihood to both control-groups, as reported by other authors 28,30,34,41,44-46, which may be related with the metabolic effects associated to RYGB, in line with the literature 30,34-36,47-49. Lower weight-gain per week of gestation, higher maternal age and smoking habits are other risk factors for SGA. Shorter gestational time appears as a deleterious factor of SGA, perhaps because it might be a signal of pregnancy problems. The higher prevalence of congenital malformations in post-BS women than in all-controls and obesecontrols, as reported by other authors 28,50, seems to be related to bariatric surgery itself. These findings are at variance with other studies which did not find any differences between post-BS and all-controls 51,52 and between post-BS and obese-controls 34,51. We also sought if SGA or LGA outcomes had impact on occurrence of malformations, as an indirect measure of nutritional imbalances, however no significant relationships were found (data not shown). In fact, apropos of nutritional deficits, in our sample, post-BS women had a significantly higher number and variety of prescriptions of nutritional supplements, namely vitamin D, B12, folate, iron, magnesium and multivitamins than all-controls and obese-controls (data not shown). We note that, RYGB, the bariatric procedure with a malabsorptive component in our sample, appears to be slightly less implicated as a risk factor for congenital malformations, and that the SGA outcome is not related with malformations, thus, nutritional deficits may not be the key-factor for the observed prevalence of malformations. A major strength of our work is the multivariate analysis of the differences between study and controlgroups, adjusted for factors that could influence the studied outcomes. Furthermore, our post-BS group included women who underwent different types of weight-loss surgery, in contrast to other studies 29,40,53-56. Therefore, our conclusions can be applicable to the majority of post-BS women and we were able to observe different effects between RYGB and restrictive-procedures. One of the limitations of our study is the small sample size, in particular of post-BS women, when compared to other studies 29,40,44. Therefore, it might not be powered enough to detect statistically 12 significant effects in the categories with small frequency. Further, our work implicates the expertise of one single institution, which may not be representative of the Portuguese population. Other limitations are related with this being a retrospective design 57,58. It would be interesting to make a prospective study in which we would compare pregnancy outcomes in women who would undergo bariatric surgery with women who would lose weight through a conservative way (without surgery), in order to understand the differences between weight-loss effects, metabolic-effects and surgery-effects. These conclusions would be important to define an effective follow-up strategy for women who lose weight through surgery before becoming pregnant, to avoid negative pregnancy outcomes like SGA and congenital malformations. In conclusion, bariatric surgery improves some pregnancy outcomes at the cost of degradation of other outcomes. 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Emergency medicine journal 2003;20:54-60. Anexos março, 2019 1. Aprovação da Comissão de Ética para a Saúde 2. Normas da Revista: Obstetrics & Gynecology °Items 16 and 18 (assumptions): Please include a Table citing all assumptions of parameter values, with justification from either references or a footnote explaining the rationale for that value. In addition, please include a description of and justification for the range of values around the parameter estimate. SQUIRE 2.0 24 (for reporting on quality improvement in health care): Please submit a copy of the SQUIRE 2.0 checklist, available at http://www.equator-network. org/reporting-guidelines/squire/,and indicate the page number where therequiredinformationis provided. CHERRIES 25 (for reporting results of Internet e-surveys): Please submit a copy of the simplified CHERRIESchecklist,availableat http://edmgr.ovid.com/ong/accounts/ cherries.pdf), and indicate the page number where the required information is provided. Obstetrics & Gynecology does not require use of other reporting guidelines. However, authors may wish to search http://www.equator-network.org for guidelines for other types of studies to facilitate complete, transparent, and accurate reporting of their work. As noted above, we ask authors to address all items recommended by the guidelines (as a minimum); where this is not possible please provide an explanation in the text to give a transparent account of your study. If there are items on the checklist that you cannot attest to, please itemize these in your cover letter with an explanation. For manuscripts that require reporting guidelines, a checklist or explanation in the cover letter must accompany the submission. The manuscript will be returned to the author if this information is not included in the initial submission. Adherence to recommended reporting guidelines will facilitate review of your manuscript, increase the probability of its successful publication, and improve the usability of research findings from your study in further research and clinical practice. Guidelines for reporting of multivariable prediction models We strongly suggest referring to “Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD): Explanation and Elaboration. 26 Often authors use a nomogram (Figure 7 in reference 26), which is a useful visual aid for showing the various model inputs, but we also encourage use of a visual display of a calibration curve (Figure 8 in reference 26). This figure allows the reader to see the relationship of observed versus predicted probabilities along the spectrum of probabilities from the data, along with confidence intervals for those prediction estimates.An added featureisthedisplay below the x-axis of the relative counts of adverse versus non-adverse outcomes. Alternatively, those could be displayed (similar to survival analysis graphs) with numerical counts of adverse versus non-adverse outcomes at the intervals referred by the graph. The advantage to this level of detail is that it would convey to the reader the strength of association at various model scores, along with their relative uncertainty, reflecting how many data were available at various cutpoints. The example cited used Stata/SE 11, but similar software is available in SPSS, SAS or R. With some work, it could also be done using Excel. L. reVITALize Data Definitions Standard obstetrics and gynecology data definitions have been developed through the reVITALize initiative, 27,28 which was convened by the American College of Obstetricians and Gynecologists and the members of the Women’s Health Registry Alliance. Obstetrics & Gynecology has adopted the use of the reVITALize definitions. Please access the definitions at these links: the obstetric data definitions are available at http://links.lww.com/AOG/A515, 27 and the gynecology data definitions are available at http://links.lww.com/AOG/ A935. 28 If use of the reVITALize definitions is problematic, please contact the editorial office at obgyn@ greenjournal.org. M. Survey Response Rates The Editors of Obstetrics & Gynecology rarely accept a survey study witharesponserateoflessthan 60%. A response rate below 60% increases the risk of a sampling error that can result in biased survey estimates. The journal infrequently makes exceptions for outstanding studies, and only when non-responders have been well-characterized and there is clear evidence that non-response is not linked to the information sought in the survey. The authors need to demonstrate that respondents were representativeofallthosewhowereeligibleto take the survey. N. Transparent Peer Review Obstetrics & Gynecology employs a single-blind peer-review process in which the authors do not know the identity of the reviewers unless the reviewer voluntarily self-identifies. Starting in 2018, the journal is making efforts toward increasing transparency around the peer review process. This will occur in two areas (accepted articles, only): The dates of submission, revision, and acceptance will be published in the article acknowledgments. The peer reviewers’and editor’s comments to the author, along with the authors’responses to these comments, will be published as supplemental digital content to the online version of the article. Reviewers will not be identified by name. The iterative communication from the editor to the authors will also be published so that interested readers can see the process of moving amanuscriptfromsubmissionto 198 Instructions for Authors OBSTETRICS & GYNECOLOGY publication. Authors can opt out of having their responses to these comments published if they wish to do so. However, even if the authors decline to have their responses published, the reviewer and editor comments will be posted online. II. ARTICLE FORMATS Several types of articles can be submitted for publication in Obstetrics & Gynecology: Original Research, Case Reports, Systematic Reviews, Current Commentaries, Executive Summaries, Consensus Statements, Guidelines, Clinical Practice and Quality, Procedures and Instruments, Personal Perspectives, Clinical Conundrums, Questioning Clinical Practice, and Letters. Select article types, such as Editorials and Clinical Expert Series articles, are solicited by the Editors. Stated page limits in II. A–J include all numbered pages in a manuscript (ie, title page, précis, abstract, text, tables, boxes, and figure legends). Checklists, the cover letter, and figures do not contribute to the page limits. See also Table 1. A. Original Research An original research article is a fulllength report of an original clinical or basic investigation. Length should not exceed 5,500 words (approximately 22 manuscript pages; see Table 1). 1) Abstract: Original research reports should have a structured abstract of no more than 300 words, using the following headings:* Objective: Main question, objective, or hypothesis (single phrase starting with, for example, “To evaluate...”or “To estimate.”[never start with “To determine.”]). Methods: Study design, participants, outcome measures, and, in the case of a negative study, statistical power. Results: Measurements expressed in absolute numbers and percentages, and when appropriate indicaterelativerisksoroddsratios with confidence intervals and level of statistical significance; any results contained in the abstract should also be presented in the body of the manuscript, tables, or figures. Conclusion: Directly supported by data, along with clinical implications. Clinical Trial Registration: Registry name,URL,andregistration number (if applicable). Notethatabstractsforrandomized controlled trials should be structured similarly to the provided example (see http://edmgr.ovid.com/ong/accounts/ sampleabstract_RCT.pdf )andshould include the primary outcome and sample size justification in the Methods. The Results should begin with the dates of enrollment to the study, a description of demographics, and the primary outcome analysis. 2) Headings: Organize original research reports in a manner similar to their structured abstract. † Table 1. Manuscript Length At A Glance Article Type Abstract Length Manuscript Word Count * Maximum Number of References † Original Research 300 words 5,500 words (;22 pages) ‡ 60 Case Report 125 words 2,000 words (;8 pages) 8 Systematic Review 300 words 6,250 words (;25 pages) 120 Current Commentary 250 words 3,000 words (;12 pages) 24 Executive Summaries, Consensus Statements, and Guidelines 250 Words NA § NA § Clinical Practice and Quality 300 words 5,500 words (;22 pages) ‡ 60 Procedures and Instruments 200 words 2,000 (;8 pages) 10 Personal Perspectives NA 3,000 words (;12 pages) NA k Clinical Conundrums NA 1,500 words (;22 pages) 8 Questioning Clinical Practice NA 1,500 words (;22 pages) 8 Letters NA 350 words 5 ;, approximately; NA, not applicable. * Manuscript length includes all numbered pages in a manuscript (ie, title page, précis, abstract, text, tables, boxes, figure legends, and appendixes). Manuscript pages should be double-spaced. † Suggested limit. ‡ The Introduction should not exceed 250 words; the Discussion should not exceed 750 words. § Authors should attempt to be concise and limit the page length and number of references to what is required to sufficiently discuss the topic. k References are generally not needed in Personal Perspectives articles. *Manuscripts that have industry funding must add an additional heading, “Funding Source,” which should contain an abbreviated listing of the funders. † Manuscripts that have industry funding must include the heading, “Role of the Funding Source,”before the Methods. This section should contain a detailed description of the sponsor’s role as well as the language specified in part I.E. VOL. 133, NO. 1, JANUARY 2019 Instructions for Authors 199 Introduction: Orients the reader to the problem(s) addressed by the report, preferably in one page or less, and clearly states the hypothesis or objective of the research. Avoid a detailedliteraturereviewinthissection. Methods: States the type of study conducted, and describes the research methodology in sufficient detail so that others could duplicate the work. This section should state that an appropriate IRB approved the research (or that the research wasexemptfromapproval)and that the participants gave informed consent. In all cases, the complete name of the IRB should be provided in the manuscript. Identify methods of statistical analysis and, when appropriate, state the basis (including alpha and beta error estimates) for their selection. Cite any statistical software programs used in the text. In most cases, express P values to no more than three decimal places. Indicate your study’s power to detect statistical difference. For administrative database studies, identify who entered the dataand describe how the accuracy of the database was validated. Authors of clinical trials should include a data sharing statement in aboxattheendoftheMethods(see I.B). Results: Presents the findings in appropriate detail. Tables and figures may be used, but take care to minimize duplication between the text and tables or figures. Both clinical studies (observational or randomized) must include a flow diagram describing patient accrual or inclusion. Authors should report outcome data as both absolute and relative effects since information presented this way is much more useful for clinicians. Actual numbers and percentages should be given in addition to odds ratios or relative risk. When appropriate, number needed to treat for benefits (NNTb) or harm (NNTh) should be supplied. 29,30 When comparing the cost of two procedures, please express the outcome of the comparison in U.S. dollar amounts. Discussion: Begin with a description ofwhat yourstudyfound in relation to the purpose or objectives as stated in the Introduction. Address the primary outcome first, followed by the secondary outcomes (if appropriate). Describe rather than repeat results given earlier. Your findings should be compared to previous studies with explanations in cases where they differ, although acompletereviewoftheliterature is not necessary. Comment on the limitations of your study. Clearly state the importance of these findings to clinicians and actual patient care. Although some degree of speculation as to the importance of the observations is permissible, avoid making conclusions unrelated to the data presented. Primacy claims purporting that your study is the first or largest of its type should either be supported by a description of your search strategy or omitted. A final summary is not necessary, as this information should be provided in the abstract and the first paragraph of the Discussion. Although topics that require future research can be mentioned, it is unnecessary to state that “further research is needed.” B. Case Reports A case report is a brief description of up to three cases of a particular condition that reports an unusual case presentation or novel diagnostic or therapeutic approach. Length should not exceed 2,000 words (approximately 8 manuscript pages; see Table 1). Write the Propensity Score Matching In studies that are not randomized trials, often the groups being compared have baseline differences in some characteristics. Some of these characteristics may plausibly affect the probability of the adverse outcome(s). Often, mathematical modeling tools such as adjustment of an odds ratio or relative risk are used to mitigate the effect of those baseline differences. However, a problem can arise when the number of adverse events is low in relation to the number of variables used in the adjustment model. Basically, there can be insufficient information to adjust for the variables at hand, making the resulting model “overfitted.” That is, the model output contains more parameters than is justified by the data. The model may conform to the data at hand, but it is not reliably generalizable. There are several ways to address this limitation. One may be able to design the study, based on the presumed rates of adverse outcomes, to have sufficient sample sizes to allow for several potential adjustors. Alternatively, the adjustment model could be supplemented with a matching algorithm (eg, propensity score matching) to create cohorts that are statistically equivalent at baseline. We encourage authors to address this potential limitation both in the design and analysis phases of their studies, believing this approach would strengthen their submission. PValues vs Effect Size and Confidence Intervals While Pvalues are a central part of inference testing in statistics, when cited alone, often the strength of the conclusion can be misunderstood. Whenever possible, the preferred citation should be in terms of an effect size, such as odds ratio or relative risk or the mean difference of a variable between two groups, expressed with appropriate confidence intervals. When such syntax is used, the Pvalue has only secondary importance and often can be omitted or noted as footnotes in a Table format. Putting the results in the form of an effect size makes the result of the statistical test more clinically relevant and gives better context than citing Pvalues alone. 200 Instructions for Authors OBSTETRICS & GYNECOLOGY case in a way that preserves the confidentiality of the participants. The report should have a clear purpose and teaching point; simply being the first case reported does not usually justify publication. 1) Abstract: Case reports should have a structured abstract of no more than 125 words, using the following headings: Background: Importance of the subjectmatterandspecificpurpose of the report. Case(s): Summary of pertinent features of the clinical findings, important laboratory abnormalities, treatment, and outcome. Conclusion: Summary of the principal finding and why it is unique or worthy of mention, indicating relevance to clinical practice. 2) Teaching Points: Please include alistofonetothreelessonsforclinical management that derive from your manuscript. 3) Headings: Case report articles have three basic components: Introduction: Gives a brief background about why the case is important. Case(s): Describes the case(s) in a narrative format and includes the essential findings and patient management. Discussion: Includes a brief review of the literature but focuses primarily on the clinical implications of the case(s) presented. C. Systematic Reviews A systematic review article is a comprehensive review of publications relating to a specific clinical subject accompanied by critical analysis and conclusions. For author-initiated manuscripts, we only accept systematicreviews and meta-analyses.Ifyou are considering submitting a general review (not a systematic review or meta-analysis), please contact the Editor first at [email protected]. Authors must search, at a minimum,MEDLINEandClinicalTrials. gov (www.clinicaltrials.gov). The manuscript should not exceed 6,250 words (approximately 25 pages; see Table 1). Systematic review articles must follow the PRISMA 19,20 or MOOSE 22 guidelines (http://ong. editorialmanager.com) and the appropriate checklists and flow diagrams must be submitted, as applicable. Finally, as of January 1, 2020, authors of systematic reviews must prospectively register their study in PROSPERO (https://www. crd.york.ac.uk/PROSPERO/), an international database of prospectively registered systematic reviews. Please refer to the PROSPERO registration number in your submitted cover letter, and include it at the end of the abstract. 1) Abstract: Systematic review articles should have a structured abstract of no more than 300 words, using the following headings: Objective: Statement of purpose of the review. Data Sources: Sources searched, including dates, terms, and constraints. Methods of Study Selection: Number of studies reviewed and selection criteria, as well as any software used to assist with the review process. Tabulation, Integration, and Results: Guidelines for extracting data, methods of correlating, and results of review. Conclusion: Primary conclusions and their clinical applications. 2) Headings: Review articles should be organized in a manner similar to their structured abstract. Introduction: Indicates why the topic is important and states the specific objective(s) of the review. Sources: Identifies what was searched and how; if a computerized system was used, specify the dates searched, the language(s) covered, and the search terms used. Study Selection: Identifies the numberand nature of reportsreviewed, the basis of any selection (ie, exclusion and inclusion criteria), and the reports in the final tabulation. Results: Describes how observations across studies were tabulated and integrated into a cohesive whole. Discussion: Includes what can be concluded from the review, along with clinical implications and need for additional research. D. Current Commentary Current Commentary essays address issues, opinions, experiences, or perspectives of clinical relevance to the fieldofobstetricsandgynecologyand obstetrician–gynecologists. Length should not exceed 3,000 words (approximately 12 manuscript pages; Table1).Theabstractshouldbe a single paragraph that states what was done, what was found, and what the findings mean. Headings are not necessary in the body of the article but may be used if needed. E. Executive Summaries, Consensus Statements, and Guidelines Executive summaries, consensus statements, and guidelines should be submitted as drafted by their respective author groups or organizations. Authors should attempt to be concise and limit the page length to what is required to sufficiently discuss the topic. The abstract should be a single paragraph that states what was done, what was found, and what the findings mean. Headings are not necessary in the body of the article but may be used if needed. F. Clinical Practice and Quality A Clinical Practice and Quality study article is a full-length report of the implementation of research findings into clinical practice, assessment of a change in clinical practice methods on outcomes, VOL. 133, NO. 1, JANUARY 2019 Instructions for Authors 201 discussion of cost-conscious care, or a focused description of a quality improvement or a quality assessment program. Quality improvement and quality assessment studies are initiatives within a clinical unit or health care system that are designed to improve health care in terms of one or more of the aims for the health care system put forth by the Health and Medicine Division of the National Academies of Sciences, Engineering, and Medicine (formerly the Institute of Medicine): safe, effective, patient-centered, timely, efficient, and equitable. The article’slengthshouldnot exceed 5,500 words (approximately 22 manuscript pages; see Table 1). The Introduction and Discussion shouldnotexceed250wordsand 750 words, respectively. If the IRB at your institution does not require approval of quality improvement studies for either the performance or reporting of the results, please submit a copy of this decision by your IRB. Otherwise, please provide the name of the IRB that approved your study and include it in the Methods section. Clinical Practice 1) Abstract: Articles that focus on clinical practice should have a structured abstract of no more than 300 words, using the following headings: Objective: A single phrase stating the primary objective, question or hypothesis starting with, for example, “To evaluate”or “To estimate.” Methods: Describes the clinical setting, the intervention(s) or practice pattern(s) studied, study design and power calculations if appropriate, participants, and outcome measures. Results: Reports observed associationsbetweenthe interventionsand relevant contextual elements and the primary outcome(s), and important secondary outcomes when appropriate. Provides measurements expressed in absolute numbers and percentages and when appropriate indicates relative risks or odds ratios with confidence intervals and level of statistical certainty. Any results contained in theabstractshouldbealsobepresentedinthebody, tables,orfigures of the manuscript. Conclusion: Describes key findings or conclusions. Is directly supported by the data. Provides clinical implications when appropriate. 2) Headings: Clinical practice study reports should be organized in a manner similar to the structured abstract. Introduction: Orients the reader to the clinical setting and research finding(s) implemented into practice or the clinical practice method being assessed. Ends with a clearly stated primary outcome or hypothesis, followed by secondary outcomes if appropriate. Avoid a detailed literature review in this section. Methods: States the type and timeframe of study of the study and describes the research methodology in sufficient detail so that others could duplicate or adapt the work to their settings. This section should state that an appropriate IRB approved the work or determinedthework tobeexempt. If it was exempt from IRB approval, state the reason why. In all cases, the institutional affiliation of the IRB should be provided. Identify methods of statistical analysis and when appropriate, state the bases (including alpha and beta error estimates) for their selection. Cite any statistical software programs used in the text. In most cases, express Pvalues to no more than three decimal places. Where appropriate, indicate the study’sintended power to detect statistical differences in the primary outcome, and prespecified key secondary outcomes. For studies that include data obtained from administrative database, identify whoenteredthestudyandhowthe accuracy of the database was validated. Results: Presents the findings in appropriate detail. Tables and figures may be used and should be able to be understood on their own; duplication between these and the text should be minimized. Actual numbers and percentages should be given in addition to odds ratios or relative risks. When appropriate, number needed to treat for benefit (NNTb) or harm (NNTh) should be supplied. Discussion: Begins with a description of, without detailed repetition of, what the submitted study found in relation to the study’sprimary outcomes first, followed by any secondary outcomes. Describes, but does not repeat, the results. Describes how the research implementation or clinical practice change affected care, costs, workflow, or satisfaction for patients, health care providers, or the health care system(s). The discussion should compare the study’s findings with those of previous relevant studies, with explanations in cases where they differ, avoiding a complete review of the literature. Primacy claims indicating that the study is the “first”or “largest” should be avoided, unless supported by a description of the search strategy to support the claim. A final summary is not necessary. Quality Improvement and Assessment 1) Abstract: Articles describing quality improvement and quality assessment should have a structured abstract of no more than 300 words, with the following headings: Objective: Describes the nature and significance of the local problem and the purpose of the project and 202 Instructions for Authors OBSTETRICS & GYNECOLOGY thisreport(innomorethantwo sentences). Methods: Describes the clinical setting, intervention(s), approach chosen, measures for reporting the processes and results, and analytic methods. Results: Reports observed associations between the interventions and relevant contextual elements and the primary outcome(s), and important secondary outcomes when appropriate. Provides measurements expressed in absolute numbers and percentages and when appropriate indicates relativerisksoroddsratioswithconfidence intervals and level of statistical certainty. Any results contained in the abstract should be also be presented in the body, tables, or figures of the manuscript. Discussion: Describes key findings or conclusions. Is directly supported by the data. Provides clinical implications when appropriate. 2) Headings: Quality improvement and quality assessment studies should be organized in a manner similar to the structured abstract and should use elements found in the SQUIRE 2.0 reporting guideline. 24 A completed checklist should be submitted. Introduction: Describes why the study was performed and includes the nature and significance of the local problem, the framework used to explain the problem, and the assumptions used to develop the intervention. Ends with a clearly stated purpose of the project with a clearly stated primary outcome or hypothesis. Avoid a detailed literature review in this section. Methods: Describes the contextual elements such as the clinical setting (eg, inpatient versus outpatient, size of unit, purpose of the clinical setting, number and type of staff and patients, hospital vs non-hospital setting), and time frame of study. Describes the intervention in sufficient detail so that others could adapt the work to their settings, and describes the specifics of the team involved. Describes the measures for studying the processes and outcomes, data collection, and analytic methods. Identifies methods of statistical analysis and when appropriate, states the bases (including alpha and beta error estimates) for their selection. Cite any statistical software programs used in the text. In most cases, express Pvalues to no more than three decimal places. Where appropriate, indicate the study’s intended power to detect statistical differences in the primary outcome, and pre-specified key secondary outcomes. For studies that include data obtained from administrative database, identify who entered the study and how the accuracy of the database was validated. This section should state that an appropriate IRB approved the work or determined the work to be exempt. If it was exempt from IRB approval, state the reason why. In all cases the institutional affiliation of the IRB should be provided in the manuscript. Results: Reports the initial steps of the intervention and their evolution over time; details of the process measures and outcomes in appropriate detail. Tables and figures may be used and should be able to be understood on their own; duplication between these and the text should be minimized. Actual numbers and percentages should be given in addition to odds ratios or relative risks. When appropriate, number needed to treat for benefit (NNTb) or harm (NNTh) should be supplied. The report should include information regarding unintended outcomes and details about missing data. Finally, the report should address racially equitable outcomes. 31 Discussion: Describes the key findings, relevance to the rationale and specific aims of the study and particular strengths of the study. Describestheassociationsbetweenthe intervention and the outcomes and considers the approach used to establishwhetherornotacause-effect relationship was established. The discussion should compare the study’s findings with those of previous relevant studies with explanations in cases where they differ; avoiding a complete review of the literature. Primacy claims indicating that the study is the “first”or “largest”should be avoided, unless supported by a description of the search strategy to support the claim. Considers outcomes in terms of the framework for quality assessment from the Health and Medicine Division of the National Academies of Sciences, Engineering, and Medicine (formerly the Institute of Medicine). Considers the costs and strategic trade-offs involved in the intervention and the limitations of study, including generalizability, andhowtheachievedgainscanbe sustained or spread to other contextsinthecurrentorothersettings. Includes ethical aspects of the work and how these were addressed. A final summary may suggest next steps if appropriate. G. Procedures and Instruments Procedures and Instruments articles detail novel methods or applications ofmethods,treatments,interventions, instruments, or applications of instruments for clinical care or research in obstetrics and gynecology. Length should not exceed 2,000 words (approximately 8 manuscript pages; Table 1). Authors are strongly encouraged to include a video suitable for posting on the Obstetrics & Gynecology website. 1) Abstract: Procedures and Instruments articles should have a structured abstract of no more VOL. 133, NO. 1, JANUARY 2019 Instructions for Authors 203 than 200 words, using the following headings: Background: Information as to why the technique may be important. Instrument, Method, or Technique (choose one): A summary description of what is being reported. Experience: A summary of the author’s experience with the technique. Conclusion: A simple statement of what can be concluded from the report. 2) Headings: Procedures and Instruments articles have four components: Introduction: Outlines the need for the new development. Method or Technique (choose one): Describes the innovation, usually with illustrations and video. Experience: Reports experience with the technique and what the general outcomes were. Discussion: Describes the implications of the findings. H. Personal Perspectives Personal Perspectives essays offer insights into the practice of medicine, with an emphasis on the unique physician–patient relationship. Essays from various viewpoints—physician, nurse, patient—are welcome. A short essay for light reading addressing a topic pertinent to the discipline, including humor or satire, is also appropriate for this section. Poetry may also be considered. Length should not exceed 3,000 words (approximately 12 manuscript pages; Table 1). Abstracts are not included in this feature, and headings are not needed in the body of the article. I. Clinical Conundrums The Clinical Conundrums feature focuses on a specific clinical question that the obstetrician–gynecologist faces in day-to-day clinical practice for which evidence for diagnosis, management options, or prognosis aredeficient. The intent ofthisfeature is not to do an exhaustive review of a topic but to concentrate on that one query that has no straightforward answer (ie, a clinical conundrum) and toprovideareasonablecourseofaction. Length should not exceed 1,500 words (approximately 6 manuscript pages; Table 1). There is no abstract. 1) Headings: Clinical Conundrums have four components: Clinical Vignette: Abrief,1–3sentence description of the clinical dilemma. The Conundrum: Describes the clinical problem. The Data: Discussioninresponse to 3 questions: °How should the patient be evaluated? °What is the evidence to counsel your patient? °What is a reasonable course of action? The Bottom Line: Abriefconclusion based on the available data. Clinical Conundrums is an invited feature. However, if you are interested in submitting a Clinical Conundrums article, please submit abriefproposaltotheeditorialoffice at [email protected]. J. Questioning Clinical Practice The Questioning Clinical Practice feature examines tests or procedures thathave becomethestandardofcare in obstetrics and gynecology despite alackofevidencetosupporttheiruse or the availability of better or less expensiveoptions.Lengthshouldnot exceed 1,500 words (approximately 6 manuscript pages; Table 1). There is no abstract. 1) Headings: Questioning Clinical Practice articles have four components: Clinical Vignette: Abrief,1–3sentence description of the clinical dilemma. Current Practice: Describes current practice around the test or procedure. WhyDoWeDo[Topic]? The Data: Discussion in response to 4 questions: °How did this practice get started? °How is it used to make decisions about the patient’s care? °What’s the cost of the procedure or test? °Are there alternatives? The Bottom Line: A brief conclusion based on the available data. If you are interested in submitting a Questioning Clinical Practice article, please submit a brief proposal to the editorial office at obgyn@greenjournal. org. K. Letters Letters posing a question or challenge to an article appearing in Obstetrics & Gynecology within 8 weeks of the article’s print publication will be considered for publication. Letters received after 8 weeks will rarely be considered. Submit letters at http://ong. editorialmanager.com (Editorial Manager). Letters are limited to a maximum of 350 words, including signatures and 5 references. A word count should be provided. A corresponding author should be designated. All authors’full names, degrees, and affiliations (including city, state, and country) should be included. The corresponding author’s address, telephone number, and email address should appear at the end of the letter. Letters will be published at the discretion of the Editor. The Editor may send the letter to the authors of the original article so their comments may be published simultaneously. The Editor reserves the right to edit and shorten letters. III. Stand-Alone Videos The Editors encourage the submission of videos for inclusion in 204 Instructions for Authors OBSTETRICS & GYNECOLOGY the journal’s stand-alone video gallery and on its YouTube channel. These videos will undergo review by an editor before being posted online. If you areinterested in submitting a video for consideration, please submit your written proposal to the editorial office at [email protected]. IV. COVER LETTER STRUCTURE Each manuscript should include a cover letter to the Editors addressing the following points: a. The authors’intent to submit solely to Obstetrics & Gynecology (see I.J) b. Verification that the manuscript is not under consideration elsewhere, and indication from the authorsthatitwillnotbesubmitted elsewhere unless a final negative decision is made by the Editors of Obstetrics & Gynecology c. The declaration of transparency from the lead author (see I.A) d. Clinical trial registration, if applicable (see I.B) e. For industry-sponsored research, verification that the authors have maintained ethical and transparent publication practices as outlinedinI.E f. The name of the institutional review board (IRB) and indication of approval or exemption (see I.F) g. Verification that permission has been obtained from all persons named in the acknowledgments (see V.A) h. For case reports, verification that signed consent has been obtained from the patient(s) (see I.H) i. Previous presentation at a meeting or the posting of an earlier version on a preprint server (see I.J) j. Any explanations related to reporting guidelines discrepancies (see I.K) k. Potential cover art (see VIII) V. MANUSCRIPT STRUCTURE All manuscripts should be submitted as Microsoft Word (.doc or .docx) or Open Document word processing (.odt) files. All manuscript pages (including references, tables, and figure legends) should be double-spaced. To assist with peer review, we strongly suggest that each page and line be numbered consecutively, beginning withthetitlepage. Theuseof subheadings is discouraged in all but the most complex of manuscripts. Footnotes are not allowed except in tables or figures. For direct quotations, acknowledge the author and source. Authors must include the following in the manuscript file: A. Title Page The title page should list: 1. The manuscript title, which should contain no more than a total of 100 characters (counting letters and spaces) and should not be declarative or pose a question; do not use abbreviations or commercial names in the title. 2. All author name(s), institutional, corporate, or commercial affiliations, and up to two major degree(s). 3. Corresponding author’s name, address, telephone number, and email address (the corresponding author will be responsible for all correspondence and other matters relating to the manuscript). 4. Disclosure of any source of financial support of the study, including provision of supplies or services from a commercial organization (see sections I.D and I.E for more information). 5. Disclosure of funding received for this work from any of the following organizations: National Institutes of Health, Wellcome Trust, Howard Hughes Medical Institute, and other(s). 6. A short title of no more than 45 characters (40 characters for case reports), including spaces, for use as a running foot. 7. Acknowledgments, which should list: a. All financial support of the study (refer to sections I.D and I.E for more information). b. Any and all manuscript preparation assistance (refer to section I.A for more information). Such acknowledgments must identify the entities that provided and paid for this assistance, whether directly or indirectly. The journal strongly discourages citing an anonymous donor due to concerns about conflicts of interest. If you have questions, please contact the editorial office at [email protected]. c. All persons who contributed to the work reported in the manuscript, but not sufficiently to be authors (refer to section I.A for more information). Obtain writtenpermissionfromall individuals named in the acknowledgments. Acknowledgment permissions need not be submitted to the journal; rather, the corresponding author should keep them on file. The cover letter should include verification that permission has been obtained from all named persons. d. Information about presentation at a meeting, including the dates and location of the meeting (see section I.J). e. Information about posting of an earlier version on a preprint server, including the DOI. B. Pre ´cis On the second page, authors should provide a précis for use in the Table of Contents. The précis isasinglesentenceofnomorethan 25 words that states the conclusion(s) VOL. 133, NO. 1, JANUARY 2019 Instructions for Authors 205 of the report (ie, the bottom line). Theprécisshouldbesimilartothe abstract’s conclusion. Do not use commercial names, abbreviations, or acronyms in the précis. C. Abstract Abstracts should appear on the third page of the manuscript. All informationintheabstractshould be consistent with the information in the text, tables, or figures. Avoid use of commercial names in the abstract. See Section II for more information on how to format the abstract based on article type. TheEditorsencouragetheauthors of case reports to also consider submitting a video abstract, highlighting the teaching points in their article. Samplevideoabstractsmaybeviewed online: http://journals.lww.com/green journal/Pages/collectiondetails.aspx? TopicalCollectionId5111. D. Text The main body of the article appears after the abstract. See Section II for more information on how to format the body based on article type. Consecutive line numbering should be used throughout the text. Authors should also keep the following style considerations in mind: Abbreviations and Acronyms. Only standard abbreviations and acronyms are allowed. A selected list is availableonlineathttp://ong. editorialmanager.com.Abbreviations and acronyms cannot be used in the title or précis. Abbreviations and acronyms must be spelled out the first time they are used in the abstract and again in the body of the manuscript. Commercial Names. The commercial name (with the generic name in parentheses) may be used once in the body of the manuscript; use the generic name at each mention thereafter. Commercial names should not be used in the title, précis, or abstract. E. References Use references found published in peer-reviewed publications that are generally accessible. Unpublished data, personal communications, statistical programs, papers presented at meetings and symposia, abstracts, letters, and manuscripts submitted for publication cannot be listed in the references. Information from such sources may be cited, if necessary, in the text with the sources given in parentheses. Manuscripts accepted by peer-reviewedpublicationsbutnotyet published (“in press”)arenotacceptable as references. References are numbered consecutively in the order in which they appear in the text (note that references should not appear in the abstract) andlisteddouble-spacedatthe end of the manuscript. The preferred method for identifying citations is using superscript, but citations that are cited on the line within parentheses are also acceptable. Authors are responsible for the accuracy of all references. Examples of specific types of references are available online (http://ong. editorialmanager.com). F. Tables Authors are strongly encouraged to become familiar with the format of tables published in Obstetrics & Gynecology by reviewing recently published tables. For more information onhowtoformatyourtablesforthe journal, see the tables checklist online at http://edmgr.ovid.com/ong/ accounts/table_checklist.pdf. G. Figure Legends Each piece of art should have an accompanying legend. For purposes of the initial submission and peer review process, please include each legend with its figure on a separate page of the manuscript. A sentence or two is usually sufficient. Identify any abbreviations or symbols in the legend. In the case of photomicrographs, provide magnification and stain data. VI. FIGURES At first submission, please submit your figures with their accompanying figure legends within the manuscript. If your manuscript is peer reviewed and deemed potentially acceptable for publication, you will be asked to submit your figures as individual files separate from the manuscript file in Editorial Manager. Source files, EPS or PDF files, or higher resolution TIFFs may be requested. Art that is low resolution, digitized, adapted from slides, or downloaded from the Internet will not reproduce well. Graphs created in Microsoft Word, PowerPoint, or Excel should be submittedas.docor.docx,.xlsor .xlsx, or .ppt or .pptx files. Original, high-resolution, or editable files are needed. Unacceptable art may be redrawn or removed from the article. Refer to the digital art guidelines and artwork checklist on the journal’swebsitefor more direction on digital art preparation and examples of acceptable art (http://ong.editorialmanager.com). VII. SUPPLEMENTAL DIGITAL CONTENT Authors may submit supplemental digital content to enhance their article’s text. All supplemental digital content will be reviewed by the Editors and editorial staff before posting. Supplemental digital content may include the following types of conSupplemental Digital Content (SDC) File Types Text files and tables: .doc, .docx, .odt, .xls, .xlsx, .ppt, or .pptx Figures, graphics, and illustrations: .tif, .eps, .ppt, .jpg, .pdf, or .gif Audio files: mp3 or .wav (.wav not acceptable if the file exceeds 10 MB) Video files: .wmv, .swf, .flv, .mov, .qt (.qt not acceptable if the file exceeds 10 MB), .mp4, .avi, .mpg, .mpeg, or .m4v 206 Instructions for Authors OBSTETRICS & GYNECOLOGY tent: text documents, graphs, tables, figures, graphics, illustrations, audio, PowerPoint, and video. Content should be original and not posted elsewhere. A. Guidelines for Supplemental Digital Content Cite all supplemental digital content consecutively in the text as “Appendix 1,”“Appendix 2,”etc. Provide a legend for supplemental digital content at the end of the text. List eachlegendintheorderinwhichthe material is cited in the text. The legends must be numbered to match the citations from the text (eg, “Appendix 1,”“Appendix 2,”etc.). For audio and video files, include the author name, title, brief summary of the content, videographer name, participants, length (minutes), and size (MB). Authors should ensure that patients are not identifiable in the supplemental digital content unless they obtain written consent from the patients and document that they have obtained consent in the cover letter submitted with the manuscript. B. Submission of Supplemental Digital Content When submitting supplemental digital content online to Editorial Manager, the digital files should be uploaded along with your other submission items. C. File Size and Types To ensure a quality experience for those viewing supplemental digital content, the journal’s publisher suggests that authors submit supplemental digital files no larger than 10 MB each. The exceptions to this ruleareaudioorvideofiles,whichare acceptable up to 100 MB. See the box (page 206) for a list of acceptable file types for supplemental digital content. VIII. COVER ART For each issue, the Editors may select a piece of art from the issue to be placed on the cover of the journal. This art may consist of informative illustrations, photographs, diagrams, or clinical images. Authors who believe that their submission includes potential cover art should note this fact in their cover letter. TheEditorsalsowelcomesubmissions of potential cover art via email ([email protected]). REFERENCES 1. Wager E, Barbour V, Yentis S, Kleinert S; COPE Council. Retraction guidelines. 2009. Available at: http:// publicationethics.org/files/retraction% 20guidelines_0.pdf. Retrieved October 31, 2018. 2. International Committee of Medical Journal Editors. Recommendations for the conduct, reporting, editing, and publication of scholarly work in medical journals. Defining the role of authors and contributors. Available at: http://www. icmje.org/recommendations/browse/ roles-and-responsibilities/defining-therole-of-authors-and-contributors.html. Retrieved October 31, 2018. 3. Altman DG, Moher D. Declaration of transparency for each research article. BMJ 2013;347:f4796. 4. Roberts LW. Addressing authorship issues prospectively: a heuristic approach. Acad Med 2017;92:143–6. 5. Editorial Policy Committee, Council of Science Editors. CSE’s white paper on promoting integrity in scientific journal publications. Wheat Ridge (CO): Council of Science Editors; 2018. Available at: https://www.councilscienceeditors.org/ resource-library/editorial-policies/whitepaper-on-publication-ethics/. Retrieved October 31, 2018. 6. Schulz KF, Altman DG, Moher D; for the CONSORT Group. CONSORT 2010 statement: updated guidelines for reporting parallel group randomized trials. Obstet Gynecol 2010;115:1063–70. 7. DeAngelis CD, Drazen JM, Frizelle FA, Haug C, Hoey J, Horton R, et al. Clinical trial registration: a statement from the International Committee of Medical Journal Editors. JAMA 2004;292:1363–4. 8. International Committee of Medical Journal Editors. Clinical trials registration. Available at http://www.icmje.org/abouticmje/faqs/clinical-trials-registration/. Retrieved October 31, 2018. 9. National Institutes of Health Office of Extramural Research. NIH’s definition of a clinical trial. Available at https://grants. nih.gov/policy/clinical-trials/definition. htm. Retrieved October 31, 2018. 10. Taichman DB, Sahni P, Pinborg A, Peiperl L, Laine C, James A, et al. Data sharing statements for clinical trials: a requirement of the International Committee of Medical Journal Editors. Ann Intern Med 2017;167:63–5. 11. Battisti WP, Wager E, Baltzer L, Bridges D, Cairns A, Carswell CI, et al. Good publication practice for communicating company-sponsored medical research: GPP3. Ann Intern Med 2015;163:461–4. 12. U.S. Department of Health and Human Services. Code of federal regulations. Title 45 Public welfare. Department of Health and Human Services. Part 46: Protection of human subjects. Available at: http://www.hhs.gov/ohrp/ humansubjects/guidance/45cfr46.html. Retrieved October 31, 2018. 13. Merriam-Webster’s collegiate dictionary. 11th ed. Springfield (MA): Merriam-Webster, Incorporated; 2003. 14. Committee on Publication Ethics. What to do if you suspect plagiarism: (a) suspected plagiarism in a submitted manuscript. Available at: https:// publicationethics.org/files/plagiarism% 20A.pdf. Retrieved October 31, 2018. 15. Committee on Publication Ethics. What to do if you suspect plagiarism: (b) suspected plagiarism in a published manuscript. Available at: https:// publicationethics.org/files/plagiarism% 20B.pdf. Retrieved October 31, 2018. 16. International Committee of Medical Journal Editors. Recommendations for the conduct, reporting, editing, and publication of scholarly work in medical journals. Available at: http://www. icmje.org/recommendations/. Retrieved October 31, 2018. 17. von Elm E, Altman DG, Egger M, Pocock SJ, Gøtzsche PC, Vandenbroucke JP; for the STROBE initiative. The strengthening the reporting of observational studies in Epidemiology (STROBE) statement: guidelines for reporting observational studies. Lancet 2007;370:1453–57. 18. Vandenbroucke JP, von Elm E, Altman DG, Gøtzsche PC, Mulrow CD, Pocock SJ, et al. Strengthening the reporting of observational studies in epidemiology (STROBE): explanation and elaboration. PLoS Med 2007;4:e297. doi: . 19. Moher D, Liberati A, Tetzlaff J, Altman DG; the PRISMA Group. Preferred Reporting Items for Systematic Reviews and Meta-Analyses: The PRISMA Statement. Ann Intern Med 2009;151:264–9. 20. Zorzela L, Loke YK, Ioannidis JP, Golder S, Santaguida P, Altman DG, Moher D, Vohra S; PRISMA Harms Group. PRISMA harms checklist: improving harms reporting in systematic reviews. BMJ 2016;352:i157. VOL. 133, NO. 1, JANUARY 2019 Instructions for Authors 207