The health benefits of breastfeeding are well recognised, but breastfeeding rates worldwide remain suboptimal. Breastfeeding outcomes have yet to be explored among women who give birth to macrosomic (birthweight ≥4000 g) infants, a cohort for whom the benefits of breastfeeding may be particularly valuable, offering protection against later-life morbidity associated with macrosomia. This longitudinal prospective cohort study aimed to identify whether women who give birth to macrosomic infants are at greater risk of breastfeeding non-initiation or exclusive breastfeeding (EBF) cessation. A total of 328 women in their third trimester were recruited from hospital and community settings and followed to 4 months post-partum. Women gave birth to 104 macrosomic and 224 non-macrosomic (<4000 g) infants between 2018 and 2020. Longitudinal logistic regression models calculated odds ratios (ORs) and 95% confidence intervals (CIs) to assess likelihood of EBF at four timepoints post-partum (birth, 2 weeks, 8 weeks, and 4 months) between women who gave birth to macrosomic and non-macrosomic infants, adjusted for maternal risk (obesity and/or diabetes), ethnicity and mode of birth. Macrosomic infants were more likely to be exclusively breastfed at birth and 2 weeks post-partum than non-macrosomic infants with adjusted OR = 1.94 (95% CI: 0.90, 4.18; p = 0.089) and 2.13 (95% CI: 1.11, 4.06; p = 0.022), respectively. There were no statistically significant associations between macrosomia and EBF at 8 weeks or 4 months post-partum. Macrosomia may act as a protective factor against early formula-milk supplementation, increasing the likelihood of EBF in the early post-partum period, but rates of exclusive breastfeeding continued to decline over the first 4 months post-partum.
Keywords: birthweight; breastfeeding; feeding behaviour; infant; macrosomia; maternal health.
© 2021 The Authors. Maternal & Child Nutrition published by John Wiley & Sons Ltd.