Influence of Health Literacy on Maintenance of Exclusive Breastfeeding at 6 Months Postpartum: A Multicentre Study

Citation: Valero-Chillerón, M.J.; Mena-Tudela, D.; Cervera-Gasch, Á.; González-Chordá, V.M.; Soriano-Vidal, F.J.; Quesada, J.A.; Castro-Sánchez, E.; Vila-Candel, R. Influence of Health Literacy on Maintenance of Exclusive Breastfeeding at 6 Months Postpartum: A Multicentre Study. Int. J. Environ. Res. Public Health 2022,19, 5411. https://doi.org/10.3390/ ijerph19095411 Academic Editor: Felix Akpojene Ogbo Received: 29 March 2022 Accepted: 27 April 2022 Published: 29 April 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). International Journal of Environmental Research and Public Health Article Influence of Health Literacy on Maintenance of Exclusive Breastfeeding at 6 Months Postpartum: A Multicentre Study María Jesús Valero-Chillerón1, Desirée Mena-Tudela 1,* , Águeda Cervera-Gasch 1, Víctor Manuel González-Chordá1, Francisco Javier Soriano-Vidal 2,3,4,5 , JoséAntonio Quesada 6, Enrique Castro-Sánchez 7,8 and Rafael Vila-Candel 2,5,9 1Department of Nursing, Universitat Jaume I, Av. de Vicent Sos Baynat, 12071 Castelló, Spain; [email protected] (M.J.V.-C.); [email protected] (Á.C.-G.); vchor[email protected] (V.M.G.-C.) 2Department of Nursing, Universitat de València, 46010 Valencia, Spain; [email protected] (F.J.S.-V.); [email protected] (R.V.-C.) 3Department of Nursing, University of Alicante, 03080 Alicante, Spain 4Department of Obstetrics and Gynaecology, Hospital Luis Alcanyis, 46819 Xàtiva, Spain 5Foundation for the Promotion of Health and Biomedical Research in the Valencian Region (FISABIO-SP), 46020 Valencia, Spain 6Department of Clinical Medicine, Universidad Miguel Hernández, 03202 Elche, Spain; [email protected] 7 Health Protection Research Unit in Healthcare-Associated Infection and Antimicrobial Resistance at Imperial College London, London W12 0NN, UK; [email protected] 8College of Nursing, Midwifery and Healthcare, University of West London, Brentford TW8 9GA, UK 9Department of Obstetrics and Gynaecology, Hospital Universitario de la Ribera, 46600 Valencia, Spain *Correspondence: [email protected] Abstract: Background: International organizations recommend initiating breastfeeding within the first hour of life and maintaining exclusive breastfeeding for the first 6 months. However, worldwide rates of exclusive breastfeeding for 6-month-old infants is far from meeting the goal proposed by the World Health Organization, which is to reach a minimum of 50% of infants. Education is one of the factors affecting the initiation and continuation of breastfeeding, and incidentally, it is also related to lower health literacy. This study explored the influence of health literacy on maintenance of exclusive breastfeeding at 6 months postpartum. Methods: A longitudinal multicenter study with 343 women were recruited between January 2019 and January 2020. The first questionnaire was held during the puerperium (24–48 h) with mothers practicing exclusive breastfeeding, with whom 6-month postpartum breastfeeding follow-up was performed. Socio-demographic, clinical and obstetric variables were collected. Breastfeeding efficiency was assessed using the LATCH breastfeeding assessment tool. The health literacy level was evaluated by the Newest Vital Sign screening tool. A multivariate logistic regression model was used to detect protective factors for early exclusive breastfeeding cessation. Results: One third of the women continued exclusive breastfeeding at 6 months postpartum. Approximately half the participants had a low or inadequate health literacy level. An adequate health literacy level, a high LATCH breastfeeding assessment tool score ( >9 points ) and being married were the protective factors against exclusive breastfeeding cessation at 6 months postpartum. Conclusion: Health literacy levels are closely related to maintaining exclusive breastfeeding and act as a protective factor against early cessation. A specific instrument is needed to measure the lack of “literacy in breastfeeding”, in order to verify the relationship between health literacy and maintenance of exclusive breastfeeding. Keywords: breastfeeding; breastfeeding cessation; early weaning; exclusive breastfeeding; health literacy; nursing; women 1. Introduction Breastfeeding (BF) offers many health benefits to the mother and the BF infant, both in the short and long term [ 1 ]. For example, BF would reduce maternal and infant mortality [ 2 ] Int. J. Environ. Res. Public Health 2022,19, 5411. https://doi.org/10.3390/ijerph19095411 https://www.mdpi.com/journal/ijerph Int. J. Environ. Res. Public Health 2022,19, 5411 2 of 13 by 823,000 infants and 20,000 mothers worldwide if exclusive breastfeeding (EBF) up to 6 months was maintained [ 3 ]; BF would improve nutritional factors, lower related infant food costs [ 4 , 5 ], and contribute to family and social economic savings by lowering the prevalence of diseases in breastfed newborns (NB) [ 5 , 6 ]. BF also fosters the mother–child bond by encouraging a safe attachment [7] and a better mother–infant relationship [4]. The World Health Organization (WHO) and the United Nations International Children’s Emergency Fund (UNICEF) recommend initiating breastfeeding within the first hour of life and maintaining EBF for the first 6 months. EBF rates at 6 months are low, despite efforts by international organizations [ 8 ] to protect and promote this practice [ 9 ]. According to the Global Health Observatory data repository [ 10 ], only 25% of infants in Europe are breastfed exclusively for the first 6 months [ 11 ]. In Spain, EBF prevalence at 6 months is around 16.8%, considerably less than the ~75% EBF rate reported at hospital discharge [12,13]. There are multiple factors for the premature abandonment of breastfeeding. Among these factors, we can find the low weight of the infant, the feeling of lack of milk, smoking, the mother’s lack of knowledge about breastfeeding or the incorporation to work [ 14 , 15 ]. Education is other of the factors affecting the initiation and continuation of breastfeeding (BF) [ 9 , 16 , 17 ], and incidentally it is also related to health literacy (HL) [ 18 , 19 ]. The concept of HL emerged in the 1970s and has been continuously refined since then [ 20 , 21 ]. Health literacy is currently defined as “an individual’s ability to obtain and translate knowledge and information in order to maintain and improve health in ways that are appropriate to the individual and community context” [ 22 ]. A low HL level has been linked to difficulties understanding healthcare information and to poor therapeutic concordance, which in turn increases costs and leads to an inefficient use of healthcare resources [22,23]. Likewise, women’s HL levels can also have an effect on their children’s health during pregnancy and after birth [ 24 , 25 ]. As for the decision to breastfeed, the percentage of mothers who decide to BF rises with their HL level [ 26 ]. In one small study, health literacy was found to be a protective factor for breastfeeding [ 27 ]. Consistent with these results, the aim of this study was to explore the influence between the level of health literacy and the maintenance of exclusive breastfeeding at six months postpartum. 2. Materials and Methods 2.1. Design and Setting A longitudinal multicenter study was carried out at three hospitals in the Valencian Community (Spain): The General University Hospital of Castellón (Department of Health, Castellón); the University La Ribera Hospital (Department of Health, La Ribera); the Lluís Alcanyís Hospital of Xátiva (Department of Health, Xátiva-Ontinyent). These hospitals were either reference centers for their province (General University Hospital of Castellón and University La Ribera Hospital) or were in a rural area with large catchment populations (Lluís Alcanyís Hospital). Overall, the participating hospitals served 600,000 people. 2.2. Sample The target population comprised women registered with the Departments of Health of Castellón, La Ribera and Xátiva-Ontinyent, whose birth was at one of the participating hospitals, and who had opted for EBF on discharge. Systematic sampling of women admitted to hospital during clinical puerperium was conducted by randomly selecting one in every three puerperal women on the maternity ward every Monday. All women who wished to participate in the study were recruited, and they were asked to sign informed written consent. Mothers who were older than 18 years and had no health problems associated and/or puerperal complications at discharge were included in the study. Some situations may make it difficult to initiate lactation. For this reason, twin pregnancies, and multiple and/or premature pregnancies, and/or congenital anomalies detected in the first 24 h, and/or newborns admitted in neonatal intensive care unit were Int. J. Environ. Res. Public Health 2022,19, 5411 3 of 13 excluded [ 16 , 17 ]. We excluded women with cognitive impairments, language barriers, or illiteracy (not able to read). Illiterate women were excluded from the study as they would be unable to complete the self-administered health literacy screening tools [ 25 ]. Finally, we also excluded mothers who we were unreachable by telephone after three attempts at 6 months postpartum. We assumed that if the proportion of women with limited HL at baseline were 45%, the EBF cessation rate in the adequate HL group was 40% and, to detect a difference between groups of 15% on EBF cessation, as well as a 0.05 confidence level and 80% statistical power, 350 women were required [ 27 ]. Considering a 10% attrition rate, the final sample size was estimated at 385 women. The sample size calculation was performed by EPIDAT v.3.1, Santiago de Compostela, Spain. 2.3. Data Collection, Main Variables and HL Measure The participating hospitals attend an average of 1600 births per year in Castellón, 1400 births in La Ribera, and 700 births in Xàtiva-Ontinyent. Therefore, the number of participants in each department has been influenced by the number of births attended in each hospital. Printed questionnaires were used to collect data. Participants were recruited between January 2019 and January 2020 during clinical puerperium (24–48 h after giving birth). One researcher per participating center oversaw the first data collection, except for the HL screening tool, which women self-administered before discharge from hospital. The BF follow-up at 1, 2 and 4 postpartum months was performed by the same researcher by consulting each participants’ electronic health records. Finally, when breastfed infants were 6 months old, mothers were telephoned to document their feeding type. BF efficacy was evaluated using the LATCH breastfeeding assessment tool. This questionnaire has been validated in Spanish [ 28 ] and contains five items (“Latch”, “Audible swallowing”, “Type of nipple”, “Comfort” and “Hold–positioning”). Each item is scored numerically (0–2), where 0 is the worst possible and 2 the best possible situation. A score of 8–10 reflects effective breastfeeding. During fieldwork, BF efficacy was evaluated with this instrument by the researcher in charge at each participating hospital before hospital discharge. While contacting mothers, they were asked whether they continued EBF. If their answer was negative, they were asked about the feeding type they provided and how long they had practiced EBF. The questions were: 1. Are you still exclusively breastfeeding your baby? 2. If not, for how long did you exclusively BF your baby? Finally, feeding type information and duration were recorded in their electronic medical records. The researchers attempted a maximum of three calls per participant and followed a pre-established script to reduce data loss as much as possible and maximize data quality. Feeding type was classified as [ 16 , 29 ]: 1. EBF means that infant receives only breast milk or expressed milk; 2. Formula milk; 3. Mixed BF (combination of breast milk and formula milk). BF status was recorded at hospital discharge (48–72 h), and at 1, 2, 4 and 6 months after giving birth. Early EBF cessation was considered if it occurred before 6 months postpartum (yes/no), as set out by the World Health Organization among its 2025 targets [30]. The HL was explored through an interview at discharge and was measured by the Newest Vital Sign (NVS) questionnaire validated in Spanish, with acceptable internal consistency ( α = 0.69) [ 31 ]. This self-administered questionnaire contains six questions about a nutritional ice cream label. One point is scored per correct answer [ 32 ]. Questions are freely answered and do not lead participants to any expected response type. It classifies the HL level according to the overall score as “adequate” (4–6 points) or “limited” (<4 points). 2.4. Data Analysis A descriptive analysis was performed using absolute and relative frequencies for qualitative variables (socio-demographic and obstetric variables), and the mean and standard deviation ( ± SD) for quantitative variables. The HL-related factors and those associated Int. J. Environ. Res. Public Health 2022,19, 5411 4 of 13 with EBF cessation at 6 months were analyzed using 2 × 2 tables, the chi-squared test ( χ2 ) for qualitative variables and by comparing the means for quantitative variables via the one-factor analysis of variance (ANOVA) or the Student’s t-test, respectively. The magnitudes of the associations with EBF cessation at 6 months were dealt with by the fit of the multivariate logistic models. The odds ratio (OR) was estimated along with their 95% confidence intervals (95% CIs). A stepwise procedure based on AIC’s criterion (Akaike Information Criterion) was followed to select variables. Data analysis was performed on SPSS v.25.0 statistical package (IBM Corp. Released 2018. IBM SPSS Statistics for Windows, Armonk, NY, USA) and R (R project 2019, Version 3.5.1, Vienna, Austria). As the analysis included two variables, NVS and EBF cessation, the level of significance was adjusted by the Bonferroni method to p< 0.025. 3. Results Of 391 participants initially recruited, 48 (12.3%) were later excluded: 42 (87.5%) due to follow-up loss and six (12.5%) because they did not wish to continue in the study during follow-up. The homogeneity between those who were included and those who were excluded or lost from participation was analyzed. There were no significant differences in age, age at first pregnancy, gestational age at delivery, health literacy level by NVS or country of origin between the group that was included and the group that was excluded in this study. The final sample size was 343 women who reported EBF when discharged from hospital, and who were included in the BF follow-up until breastfed infants were 6 months old. 3.1. Socio-Demographic Characteristics The participants’ mean age was 32.5 years ( ± 5.3). The mean gestational age at birth was 39 + 3 weeks ( ± 1.1), and the mean birth weight was 3301.2 g ( ± 464.5). Table 1shows the other socio-demographic variables included in this study. Table 1. Characteristics of the included females (n = 343). n % EBF 6 months Yes 117 34.1% No 226 65.9% NVS Adequate HL level 179 52.2% Limited HL level 164 47.8% Department of Health La Ribera 216 63.0% Xátiva-Ontinyent 24 7.0% Castellón 103 30.0% Civil status Married 216 63.0% Single, separated, divorced 127 37.0% Level of education Primary or lower 97 28.3% 1st cycle, Secondary 58 16.9% 2nd cycle, Secondary 86 25.1% University diploma 40 11.7% Graduate 62 18.1% Pregnant women’s occupation Businesswoman/Professional 35 10.2% Employee 203 59.2% Unemployed 84 24.5% Not looking for a job 21 6.1% Country of origin Spain 278 81.0% Foreign 65 19.0% Int. J. Environ. Res. Public Health 2022,19, 5411 5 of 13 Table 1. Cont. n % Partner’s occupation Employee 273 79.6% Businessperson/Professional 31 9.0% Others 39 11.4% Parity One 176 51.3% Two or more 167 48.7% Skin-to-skin contact at birth No 38 11.1% Yes 305 88.9% Birth type Spontaneous 202 58.9% Instrumented 62 18.1% STC 79 23.0% Risk pregnancy Low risk 236 68.8% High risk * 107 31.2% n Mean (SD) Mother’s age (years) 343 32.5 (5.2) Age with first pregnancy (years) 343 29.8 (5.7) Gestational week at birth (weeks) 343 39.3 (1.1) LATCH score (0 to 10) 343 8.8 (0.9) Birth weight (grams) 343 3301.2 (464.5) EBF: exclusive breastfeeding; NVS: Newest Vital Sign; STC: segment transverse caesarean; LATCH: Latch audible type comfort hold. * High risk pregnancy = Preeclampsia, Gestational diabetes, Obesity, Low body mass index, Mother age > 35 years, Assisted Reproductive Treatment, Thyroid pathology, Small for gestational age, large for gestational age, fetal growth restriction, Autoimmune diseases, Previous cesarean section, Previous preterm birth and Hepatitis Virus infection. 3.2. BF-Related Variables The mean LATCH breastfeeding assessment tool score for BF efficiency was 8.8 out of 10 points ( ± 0.9). The 6-month EBF rate was 34.1% (117/343), with 65.9% (226/343) for EBF cessation before 6 months (Figure 1). Int. J. Environ. Res. Public Health 2022, 19, x 6 of 14 Figure 1. Feeding type during the study period. 3.3. HL Level Of all participants, 47.8% (164/343) had a limited HL level. The factors associated with a limited HL level were, a lower level of education (p < 0.001), being unemployed or not looking for a job (p = 0.003), and not born in Spain (p < 0.001). However, the mother’s older age (p < 0.001) was associated with a higher HL level (Table 2). Figure 2 indicates the distribution of HL levels in relation to EBF at 6 months. Table 2. Relation between HL levels (NVS) and the studied variables. Adequate HL Level Limited HL Level n % n % p-Value 1 Department of Health La Ribera 107 49.5 109 50.5 0.424 Xátiva-Ontinyent 13 54.2 11 45.8 Castellón 59 57.3 44 42.7 Civil status Married 114 52.8 102 47.2 0.775 Single, separated, divorced 65 51.2 62 48.8 Level of education Primary or lower 35 36.1 62 63.9 <0.001 1st cycle, Secondary 19 32.8 39 67.2 2nd cycle, Secondary 44 51.2 42 48.8 University diploma 32 80.0 8 20.0 Graduate 49 79.0 13 21.0 Pregnant women’s occupation Businesswoman 23 65.7 12 34.3 0.003 Employee 113 55.7 90 44.3 Unemployed 39 46.4 45 53.6 Not looking for a job 4 19.0 17 81.0 Country of origin Spain 164 59.0 114 41.0 <0.001 Foreign 15 23.1 50 76.9 Partner’s occupation Employee 148 54.2 125 45.8 0.183 Businessperson 16 51.6 15 48.4 Others 15 38.5 24 61.5 Parity One 99 56.3 77 43.8 0.122 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% At discharge 1 month 2 months 4 months 6 months Formula Mixed EBF Figure 1. Feeding type during the study period. Int. J. Environ. Res. Public Health 2022,19, 5411 6 of 13 3.3. HL Level Of all participants, 47.8% (164/343) had a limited HL level. The factors associated with a limited HL level were, a lower level of education (p< 0.001), being unemployed or not looking for a job (p= 0.003), and not born in Spain (p< 0.001). However, the mother’s older age (p< 0.001) was associated with a higher HL level (Table 2). Figure 2indicates the distribution of HL levels in relation to EBF at 6 months. Table 2. Relation between HL levels (NVS) and the studied variables. Adequate HL Level Limited HL Level n % n % p-Value 1 Department of Health La Ribera 107 49.5 109 50.5 0.424 Xátiva-Ontinyent 13 54.2 11 45.8 Castellón 59 57.3 44 42.7 Civil status Married 114 52.8 102 47.2 0.775 Single, separated, divorced 65 51.2 62 48.8 Level of education Primary or lower 35 36.1 62 63.9 <0.001 1st cycle, Secondary 19 32.8 39 67.2 2nd cycle, Secondary 44 51.2 42 48.8 University diploma 32 80.0 8 20.0 Graduate 49 79.0 13 21.0 Pregnant women’s occupation Businesswoman 23 65.7 12 34.3 0.003 Employee 113 55.7 90 44.3 Unemployed 39 46.4 45 53.6 Not looking for a job 4 19.0 17 81.0 Country of origin Spain 164 59.0 114 41.0 <0.001 Foreign 15 23.1 50 76.9 Partner’s occupation Employee 148 54.2 125 45.8 0.183 Businessperson 16 51.6 15 48.4 Others 15 38.5 24 61.5 Parity One 99 56.3 77 43.8 0.122 Two or more 80 47.9 87 52.1 Skin-to-skin contact at birth No 19 50.0 19 50.0 0.775 Yes 160 52.5 145 47.5 Birth type Spontaneous 95 47.0 107 53.0 0.068 Instrumented 38 61.3 24 38.7 STC 46 58.2 33 41.8 Risk pregnancy Low risk 115 48.7 121 51.3 0.057 High risk 64 59.8 43 40.2 n Mean (SD) n Mean (SD) p-value 2 Mother’s age (years) 179 33.5 (4.8) 164 31.4 (5.5) 0.001 Gestational week at birth (weeks) 179 39.3 (1.1) 164 39.4 (1.1) 0.765 LATCH score (0 to 10) 179 8.9 (0.9) 164 8.7 (0.9) 0.037 Birth weight (grams) 179 3281 (476.6) 164 3311 (452.2) 0.684 EBF: exclusive breastfeeding; NVS: Newest Vital Sign; STC: segment transverse caesarean; LATCH: Latch audible type comfort hold: 1Chi-square test; 2Student’s t-test. Table 3shows the relationship between the collected variables and their association with EBF cessation at 6 months. The variables associated with early EBF cessation were a limited HL level (p< 0.001), being a single, separated, divorced mother (p< 0.001), having a lower level of education (p= 0.022), and obtaining a lower LATCH breastfeeding assessment tool score (p< 0.001). Conversely, a mean score of 9.19 ( ± 0.85) for BF efficiency at hospital discharge, as measured by the LATCH breastfeeding assessment tool, presented Int. J. Environ. Res. Public Health 2022,19, 5411 7 of 13 a statistically significant association (p< 0.001) with continuing with EBF until infants were 6 months old. Int. J. Environ. Res. Public Health 2022, 19, x 7 of 14 Two or more 80 47.9 87 52.1 Skin-to-skin contact at birth No 19 50.0 19 50.0 0.775 Yes 160 52.5 145 47.5 Birth type Spontaneous 95 47.0 107 53.0 0.068 Instrumented 38 61.3 24 38.7 STC 46 58.2 33 41.8 Risk pregnancy Low risk 115 48.7 121 51.3 0.057 High risk 64 59.8 43 40.2 n Mean (SD) n Mean (SD) p-value 2 Mother’s age (years) 179 33.5 (4.8) 164 31.4 (5.5) 0.001 Gestational week at birth (weeks) 179 39.3 (1.1) 164 39.4 (1.1) 0.765 LATCH score (0 to 10) 179 8.9 (0.9) 164 8.7 (0.9) 0.037 Birth weight (grams) 179 3281 (476.6) 164 3311 (452.2) 0.684 EBF: exclusive breastfeeding; NVS: Newest Vital Sign; STC: segment transverse caesarean; LATCH: Latch audible type comfort hold: 1 Chi-square test; 2 Student’s t-test. Figure 2. Distribution of HL levels in relation to EBF at 6 months (N = 343). Table 3 shows the relationship between the collected variables and their association with EBF cessation at 6 months. The variables associated with early EBF cessation were a limited HL level (p < 0.001), being a single, separated, divorced mother (p < 0.001), having a lower level of education (p = 0.022), and obtaining a lower LATCH breastfeeding assessment tool score (p < 0.001). Conversely, a mean score of 9.19 (±0.85) for BF efficiency at hospital discharge, as measured by the LATCH breastfeeding assessment tool, presented a statistically significant association (p < 0.001) with continuing with EBF until infants were 6 months old. Table 3. Factors related to EBF cessation before 6 months. EBF 6 Months: Yes EBF 6 Months: No n % n % p-Value 1 NVS Adequate HL level 79 44.1 100 55.9 <0.001 Limited HL level 38 23.2 126 76.8 Department of Health La Ribera 65 30.1 151 69.9 0.105 Xátiva-Ontinyent 11 45.8 13 54.2 Castellón 41 39.8 62 60.2 0% 10% 20% 30% 40% 50% 60% 70% 80% Limited HL level Adequate HL level PERCENTAGE HL LEVEL NO EBF at 6 months EBF at 6 months Figure 2. Distribution of HL levels in relation to EBF at 6 months (N = 343). Table 3. Factors related to EBF cessation before 6 months. EBF 6 Months: Yes EBF 6 Months: No n % n % p-Value 1 NVS Adequate HL level 79 44.1 100 55.9 <0.001 Limited HL level 38 23.2 126 76.8 Department of Health La Ribera 65 30.1 151 69.9 0.105 Xátiva-Ontinyent 11 45.8 13 54.2 Castellón 41 39.8 62 60.2 Civil status Married 89 41.2 127 58.8 <0.001 Single, separated, divorced 28 22.0 99 78.0 Level of education Primary or lower 25 25.8 72 74.2 0.022 1st cycle, Secondary 22 37.9 36 62.1 2nd cycle, Secondary 29 33.7 57 66.3 University diploma 22 55.0 18 45.0 Graduate 19 30.6 43 69.4 Pregnant women’s occupation Businesswoman 11 31.4 24 68.6 0.850 Employee 73 36.0 130 64.0 Unemployed 26 31.0 58 69.0 Not looking for a job 7 33.3 14 66.7 Country of origin Spain 100 36.0 178 64.0 0.133 Foreign 17 26.2 48 73.8 Partner’s occupation Employee 95 34.8 178 65.2 0.330 Businessperson 7 22.6 24 77.4 Others 15 38.5 24 61.5 Parity One 58 33.0 118 67.0 0.643 Two or more 59 35.3 108 64.7 Skin-to-skin contact at birth No 9 23.7 29 76.3 0.151 Yes 108 35.4 197 64.6 Int. J. Environ. Res. Public Health 2022,19, 5411 8 of 13 Table 3. Cont. EBF 6 Months: Yes EBF 6 Months: No n % n % p-Value 1 Birth type Spontaneous 62 30.7 140 69.3 0.255 Instrumented 23 37.1 39 62.9 STC 32 40.5 47 59.5 Risk pregnancy Low risk 76 32.2 160 67.8 0.268 High risk 41 38.3 66 61.7 n Mean (SD) n Mean (SD) p-value 2 Mother’s age (years) 117 33.2 (4.5) 226 32.1 (5.6) 0.049 Gestational week at birth (weeks) 117 39.3 (1.0) 226 39.4 (1.1) 0.498 LATCH score (0 to 10) 117 9.2 (0.8) 226 8.7 (0.9) <0.001 Birth weight (grams) 117 3328 (474.7) 226 3286 (459.6) 0.637 EBF: exclusive breastfeeding; NVS: Newest Vital Sign; STC: segment transverse caesarean; LATCH: Latch audible type comfort hold: 1Chi-square test; 2Mann–Whitney test. 3.4. Variables Related to Early EBF Cessation The multivariate regression model shown in Table 4for EBF cessation before 6 months suggests that a limited HL level is associated with more than twice the probability of EBF cessation before 6 months compared to an adequate HL level adjusted by mother’s age, level education, civil status and the LATCH breastfeeding assessment tool. Both being married and obtaining a higher LATCH breastfeeding assessment tool score were also protective factors against EBF cessation before infants were 6 months old. Table 4. Multivariate logistic model for EBF cessation before 6 months. OR 95% CI p-Value NVS Adequate HL level 1 Limited HL level 2.52 (1.45–4.36) 0.001 Civil status Married 1 Single, separated, divorced, widowed 2.32 (1.34–4.01) 0.003 Level of education Primary or lower 1 1st cycle, Secondary 0.62 (0.30–1.31) 0.210 2nd cycle, Secondary 0.86 (0.43–1.73) 0.664 University diploma 0.51 (0.22–1.20) 0.124 Graduate 1.11 (0.50–2.50) 0.799 Mother’s age (years) 0.99 (0.94–1.04) 0.569 LATCH score (range 6 to 10) 0.53 (0.40–0.71) <0.001 n model = 343; n EBF cessation = 226; ROC area = 0.7401, 95% CI: 0.6868–0.7933; Likelihood Ratio Test = 58.0 (p< 0.001). NVS: Newest Vital Sign; OR: Odds Ratio; 95% CI: 95% confidence interval. 4. Discussion The present study focuses on continuation of EBF until infants are 6 months old and explores influential factors, namely HL levels. One of the WHO’s goals for 2025 is to reach EBF rates of at least 50% until infants are 6 months old [ 30 ]. Worldwide EBF rates at 6 months fall short of this recommendation [ 33 ]. Between 2006 and 2012 in Europe, it was estimated that only 25% of breastfed infants received EBF for the first 6 months of life [ 11 ]. According to the European Health Information Gateway [ 34 ], EBF rates at 6 months were 58.3% in Italy (2011), 53.9% in Portugal (2013) and 58.4% in Spain (2017). However, more recent studies carried out in Spain report considerably lower EBF infants until the age of 6 months, ranging from 16.8% [ 12 ], 21.6% [ 35 ], or 31.4% [36], to 43% [37]. Int. J. Environ. Res. Public Health 2022,19, 5411 9 of 13 Different studies have reported an association between mothers’ level of education and continuing with EBF and showing that the higher the level of education, the longer that EBF lasts [ 35 – 37 ], in line with our results. Other authors have established an association between level of education and HL levels [ 18 , 19 ]. Although it may seem that a low educational level could be associated with a low HL, this relationship does not always have to be observed [ 38 ]. A relation was also recently found between HL levels and continuing EBF in a pilot study; however, the follow-up period only covered 4 months [ 25 ]. Therefore, the present study verifies a statistically significant association between limited HL level and EBF cessation before 6 months in line with previous studies [ 27 ], and observed that the probability of EBF cessation was more than two-fold compared to the mothers with an adequate HL level. Previous studies have related found an association with mothers’ age and early EBF cessation [ 9 , 35 , 37 ]. In agreement with results hitherto reported [ 39 ], we noted a statistically significant association between being older and EBF rates at 6 months postpartum. This association might be due to ongoing family support, better socio-economic status or a higher level of knowledge about BF benefits, as other research has shown [ 40 – 43 ]. There are also reports indicating that those families with single, separated, or divorced mothers, the probability of EBF cessation before 6 months postpartum more than doubles. For continuing EBF, several studies have verified that family support [ 44 ] and having a partner are key factors [ 45 , 46 ]. Other authors have reported how the probability of EBF cessation before 6 months postpartum more than doubles in families with single, separated, or divorced mothers [ 47 , 48 ]. Women’s immediate environment (family, friends and neighbours) is the most influential social support network in shaping pregnant women’s expectations and decisions about pregnancy, labour and nursing [ 49 ]. However, the NVS tool does not incorporate those social aspects, unlike other tools such as the Health Literacy Questionnaire [ 50 ], so their influence on the HL of breastfeeding women remains to be clarified [ 51 ]. It is noteworthy that being older with a first pregnancy also showed a statistically significant association with an adequate HL level. It was not surprising that the two variables contributing to continuing EBF, namely an adequate HL level and older maternal age, were also closely interrelated, as seen in a recent study in Spain [ 43 ]. Nevertheless, future studies are needed to corroborate the relationship between being older with first pregnancy and continuing EBF and a higher HL level, and the factors that could influence the relationship between both these variables must also be explored. The average LATCH score was high with a small standard deviation, which suggests that the majority of the study population was breastfeeding effectively or nearly effectively. It is worth stressing the predictive capacity of the LATCH breastfeeding assessment tool. Different studies have measured BF efficacy both postpartum and before hospital discharge. These studies showed that BF efficacy can be effectively evaluated using LATCH [ 52 ], and its predictive performance is high at 6 weeks postpartum [ 53 – 55 ]. The present study revealed that high LATCH breastfeeding assessment tool scores were significantly associated with a lower probability—almost half—of EBF cessation before breastfed infants were 6 months. As the LATCH breastfeeding assessment tool seems to be useful, future studies should take advantage of these findings to relate the LATCH scores with continuation of EBF in the longer term. However, the LATCH could be further refined to incorporate elements such as mother/infant interaction [ 56 ]. This tool has major flaws, including the inability of the user to assign different scores per breast (e.g., if one nipple is flat and the other is everted), the lack of representation of infant’s oral anatomy and functionality. Moreover, women often seek support beyond their home if it is not available there. However, more studies need to be conducted to corroborate the association between family support and continuing EBF to 6 months. Despite the need for more robust studies to determine the association between level of health literacy and maintenance of exclusive breastfeeding at 6 months postpartum, this study shows a profile of women that should not go unnoticed by health professionals caring for women during the perinatal period. According to the results of this study, the profile