Factors associated with breastfeeding maintenance for 12 months or more: a systematic review / Fatores associados à manutenção da amamentação por 12 meses ou mais: revisão sistemática

Abstract Objective Synthesize the information about the factors associated with maintenance of breastfeeding for 12 months or more. Data source A systematic review was conducted in the Pubmed/Medline, Scielo, and Lilacs databases, including articles published in Portuguese or English since 2004 on the factors associated with breastfeeding maintenance for at least 12 months; review articles and those with qualitative design were excluded. The factors were organized into four levels, according to the chronological proximity to the outcome: distal, distal intermediate, proximal intermediate, and proximal; nationality and place/area of residence were considered contextual factors. Summary of data 1174 articles were identified, of which 19 were included in this review, comprising seven cohort studies and 12 cross-sectional studies. A total of 39 of the 75 assessed factors were associated with the outcome at least once. The factors with the highest percentages of associations with maintenance of breastfeeding for 12 months or more, considering the number of times they were tested were: children whose parents are the caregivers (100%), none type of maternal exposure to smoke (54%), children and/or parents are immigrants/foreigners (50%), live in urban areas (42.9%), older maternal age (40%), married women (37.5%), higher level of maternal education (31.3%), greater parity (30.8%), and lower income (30%). Conclusions The maintenance of breastfeeding for 12 months or more is associated with multiple factors, emphasizing the contextual factors and those related to some maternal sociodemographic characteristics. Associations differ in effect and magnitude between the different populations studied.

Resumo Objetivo Sintetizar as informações sobre os fatores associados à manutenção da amamentação por 12 meses ou mais. Fontes de dados Foi conduzida revisão sistemática nas bases de dados Pubmed/Medline, Scielo e Lilacs, inclusive artigos publicados em língua portuguesa ou inglesa desde 2004 sobre fatores associados à amamentação por, no mínimo, 12 meses. Excluíram-se artigos de revisão e com delineamento qualitativo. Os fatores foram organizados em quatro níveis de acordo com a proximidade cronológica com o desfecho: distal, intermediário distal, intermediário proximal e proximal; nacionalidade e local/área de residência foram considerados fatores contextuais. Síntese dos dados Identificaram-se 1.174 artigos, dos quais 19 foram selecionados para revisão, sete estudos de coorte e 12 transversais. Dos 75 fatores explorados, 39 mostraram-se associados ao desfecho ao menos uma vez. Os fatores com os maiores percentuais de associações com a manutenção da amamentação por 12 meses ou mais, considerando o número de vezes que foram testados, foram: filhos terem os pais como cuidadores (100%), algum tipo de exposição materna ao fumo (54%), crianças e/ou pais serem imigrantes/estrangeiros (50%), morar em zona urbana (42,9%), maior idade materna (40%), mãe ser casada (37,5%), maior escolaridade materna (31,3%), maior número de filhos (30,8%) e menor renda familiar (30%). Conclusões A manutenção da amamentação por 12 meses ou mais está associada a múltiplos fatores, com destaque para os fatores contextuais e os relacionados a algumas características sociodemográficas das mães. As associações diferem em efeito e magnitude entre as diferentes populações estudadas.

Factors associated with breastfeeding maintenance for 12 months or more: a systematic review.

OBJECTIVE: Synthesize the information about the factors associated with maintenance of breastfeeding for 12 months or more. DATA SOURCE: A systematic review was conducted in the Pubmed/Medline, Scielo, and Lilacs databases, including articles published in Portuguese or English since 2004 on the factors associated with breastfeeding maintenance for at least 12 months; review articles and those with qualitative design were excluded. The factors were organized into four levels, according to the chronological proximity to the outcome: distal, distal intermediate, proximal intermediate, and proximal; nationality and place/area of residence were considered contextual factors. SUMMARY OF DATA: 1174 articles were identified, of which 19 were included in this review, comprising seven cohort studies and 12 cross-sectional studies. A total of 39 of the 75 assessed factors were associated with the outcome at least once. The factors with the highest percentages of associations with maintenance of breastfeeding for 12 months or more, considering the number of times they were tested were: children whose parents are the caregivers (100%), none type of maternal exposure to smoke (54%), children and/or parents are immigrants/foreigners (50%), live in urban areas (42.9%), older maternal age (40%), married women (37.5%), higher level of maternal education (31.3%), greater parity (30.8%), and lower income (30%). CONCLUSIONS: The maintenance of breastfeeding for 12 months or more is associated with multiple factors, emphasizing the contextual factors and those related to some maternal sociodemographic characteristics. Associations differ in effect and magnitude between the different populations studied.

Duration of exclusive breastfeeding in a Brazilian population: new determinants in a cohort study.

BACKGROUND: Determinants of the duration of exclusive breastfeeding (EBF) differ in effect and magnitude across populations. The present study aimed to identify factors associated with discontinuation of EBF in a municipality in northeastern Brazil, including variables that have received little or no attention in previous literature. METHODS: This cohort study involved 1,344 mother-child pairs selected from maternity hospitals in Feira de Santana, Bahia, Brazil. Subjects were followed up for 6 months through monthly home visits, and discontinuation of EBF was recorded. Possible determinants were tested using Cox's four-level hierarchical survival model, taking into consideration the temporal proximity of the predisposing factors to interruption of EBF. Median duration of EBF was estimated using Kaplan-Meier's survival curve. RESULTS: Median duration of EBF was 89 days. Out of the 19 variables tested, 9 showed an association with EBF cessation; of these, two had never been evaluated in Brazilian studies, namely, mother partner's appreciation for breastfeeding (hazard ratio [HR] 0.62; 95% confidence interval [95% CI] 0.48-0.79) and limiting the number of nighttime feeds at the breast (HR 1.58; 95% CI 1.11-2.23). Another two variables that had been previously evaluated, but had never been described as determinants of discontinuation of EBF showed association: presence of cracked nipples (HR 2.54; 95% CI 2.06-3.13) and prenatal care provided by public services (HR 1.34; 95% CI 1.17-1.55). Other variables showing associations with the outcome were: guidance on breastfeeding received at the hospital (HR 0.80; 95% CI 0.68-0.92), birth in a Baby-Friendly Hospital (HR 0.85; 95% CI 0.73-0.99), less than or equal to 8 years of maternal schooling (HR 1.34, 95% CI 1.17-1.53), mother working outside the home (HR 1.73; 95% CI 1.53-1.95), and use of a pacifier (HR 1.40; 95% CI 1.14-1.71). CONCLUSIONS: The study confirmed that the factors associated with EBF duration are multiple, variable, and dependent on the population being evaluated. Characteristics that had never been previously evaluated or described, at least in Brazilian studies, behaved as determinants of EBF in the present study, and thus allow to expand the existing list of factors determining this practice.

Determinants of breastfeeding initiation within the first hour of life in a Brazilian population: cross-sectional study.

BACKGROUND: Breastfeeding within the first hour of life is a potential mechanism for health promotion. The purpose of this study was to evaluate the prevalence of breastfeeding initiation within the first hour of life in Feira de Santana, Bahia, Brazil, between 2004 and 2005, and investigate the influence of maternal, child and prenatal factors on this practice. METHODS: This is a cross-sectional study extracted from the results of a contemporary cohort conducted in 10 maternity hospitals in the city of Feira de Santana, Bahia, Brazil. A group of 1,309 mother-child pairs was included in the study. Information about mother's and baby's characteristics, pregnancy, birth, and time of breastfeeding initiation was collected in the first 72 hours after delivery, through interview with mothers and hospital records. The data gathered were stored and analyzed using the SPSS 16.0 and R 8.0. The chi-square test and binary logistic regression analysis were used to examine the relationship between breastfeeding within the first hour and different variables. RESULTS: 47.1% of the mothers initiated breastfeeding within the first hour after birth. Early initiation of breastfeeding was associated with birth at full term pregnancy (adjusted Prevalence Ratio 1.43; 95% confidence interval 1.10 to 2.00), mothers who received prenatal guidance regarding the advantages of breastfeeding (aPR1.23; 95% CI 1.11 to 1.41) and vaginal delivery (aPR 2.78; 95% CI 2.38 to 3.23). CONCLUSIONS: In order to improve the rates of breastfeeding within the first hour of life, health care professionals must promote the factors favoring this practice such as prenatal guidance regarding the advantages of breastfeeding, vaginal delivery and full term birth, and stimulate this practice in vulnerable situations such as mothers with cesarean section and preterm birth.