Breastfeeding initiation and duration and child health outcomes in the first baby study

Highlights

• Breastfeeding duration associated with fewer reported acute illnesses at 6 months

• Breastfeeding duration negatively associated with diarrheal illness/constipation

• Analyses demonstrated breastfeeding negatively associated with child BMI

• Longer breastfeeding duration resulted in lower rates of overweight/obesity

Abstract

Despite the known benefits of breastmilk, associations between breastfeeding and child overall health outcomes remain unclear. We aimed to understand associations between breastfeeding and health outcomes, including child weight, through age 3. Analysis included women (N = 3006) in the longitudinal, prospective First Baby Study from 2009 to 2014. For this analysis, breastfeeding initiation and duration were measured using self-reported data from the 1-, 6- and 12-month surveys; child illnesses were analyzed from the 6-, 12-, and 24-month interviews; height and weight at age 3 were used to determine overweight/obese (≥85th percentile) and obese (≥95th percentile). Adjusted logistic regressions were utilized to determine significance. Greater duration of breastfeeding was associated with fewer reported acute illnesses at 6 months (p < 0.001) and fewer diarrheal illness/constipation episodes at 6, 12, and 24 months (p = 0.05) in adjusted analyses. Fewer breastfed children, compared to non-breastfed children, were overweight/obese (23.5% vs. 37.8%; p = 0.032) or obese (9.1% vs. 21.6%; p = 0.012) at age 3. Breastfeeding duration was negatively associated with overweight/obese (never breastfed: 37.8%, 0–6 months: 26.9%, >6 months: 20.2%; p = 0.020) and obesity (never breastfed: 21.6%, 0–6 months: 11.0%, >6 months: 7.3%; p = 0.012). Overall, our findings support the hypothesis that duration of breastfeeding is associated with fewer reported acute illnesses at 6 months of age and diarrheal illness and/or constipation episodes at 6, 12, and 24 months. Additionally, results from our study suggest a protective effect of breastfeeding from childhood overweight/obesity, as children who received breastmilk for 6 months or longer had lower odds of overweight/obesity at age 3 years.

Introduction

Breastfeeding rates in the U.S. have steadily increased over the past decade, but remain well below the WHO Global Nutrition Targets for 2015 which established an exclusive breastfeeding target rate of 50% up to 6 months of age (Centers for Disease Control and Prevention, 2017). The 2016 National Immunization Survey indicated that only 21.9% of mothers were exclusively breastfeeding at 6 months postpartum and 29.2% were breastfeeding at 1 year (World Health Organization, 2014). The short-and long-term benefits of breastfeeding on infant health is well evidenced and includes reduced incidence of childhood illnesses, acute otitis media, severe lower respiratory tract infections, asthma, constipation, gastrointestinal infection, and eczema (Ip et al., 2007; Duijts et al., 2010; Bowatte et al., 2015; Turco et al., 2014; Silvers et al., 2012).

Although extensive research supports the medical benefits of breastfeeding, research examining the relationship between breastfeeding and infant weight has generated conflicting results (Brion et al., 2011). Over the past three decades, childhood obesity rates in America have tripled, and today, nearly one in three children in America is overweight or obese (Ogden et al., 2014). Worldwide obesity has more than doubled since 1980 and in 2014, 41 million children under the age of 5 were overweight or obese (Ogden et al., 2014). As a result of this epidemic, research on the prevention of childhood obesity, including breastfeeding research, has elicited much scientific interest (Uwawzuoke et al., 2017). Differences in overweight/obesity risk in breastfed versus non-breastfed infants are likely influenced by differences in maternal sociodemographic factors such as race and education, as well as maternal health (e.g., overweight/obesity) which is seldom reported or controlled for in published studies (Lefebre and John, 2014). Furthermore, information on duration of breastfeeding is not always reported, thus the optimal duration of breastfeeding necessary to reduce the likelihood of a child being overweight/obese remains unknown (Oken et al., 2017).

The primary aim of this secondary data analysis from the First Baby Study (FBS) was to investigate potential associations between the initiation and duration of breastfeeding on parent-reported childhood illnesses and child weight. We hypothesized that children who were breastfed for the recommended 6 months or longer, would have fewer parent reported illnesses at 6, 12, and 24 months of age and a lower likelihood of overweight/obesity at 3 years.