Megan E Jensen, Bronwyn K Brew, Jason Dizon, Elizabeth Holliday, Craig Pennell, Vanessa M McDonald, Peter G Gibson, Vanessa E Murphy
Maternal asthma was negatively associated with breastfeeding outcomes in the immediate postpartum period; associations were not explained by perinatal factors or comorbidities. Findings highlight the need for early breastfeeding support for women with asthma.
BACKGROUND: In infants born to mothers with asthma, breastfeeding may lower the risk of adverse respiratory outcomes; however, breastfeeding rates are low among this group.
OBJECTIVE: To evaluate early breastfeeding outcomes in relation to maternal asthma and determine whether observed associations were mediated by perinatal factors or varied by maternal comorbidities.
METHODS: Data on singleton births were obtained from electronic obstetric records from three local health districts in New South Wales, Australia (2018-2020). Associations between asthma and breastfeeding outcomes were assessed using robust Poisson models fitted within a generalised estimating equation framework. Perinatal factors were sequentially included in models to explore potential mediation of asthma-breastfeeding associations. Interaction between asthma and comorbidities on breastfeeding outcomes was also tested in models.
RESULTS: Among 40,151 births, 4412 (11%) were to women with asthma. Asthma was associated with slightly reduced breastfeeding initiation (adjusted relative risk [aRR]=0.98; 95% confidence interval [CI]: 0.96, 0.99); exclusive breastmilk feeding at birth (aRR=0.98; 95% CI: 0.96, 0.99) and postpartum follow-up (aRR=0.97; 95% CI: 0.94, 0.99); and increased risk of breastfeeding issues (aRR=1.07; 95% CI: 1.02, 1.11). Potential mediators (caesarean birth, preterm birth, low birthweight, neonatal hospitalisation) did not alter associations by >10% for breastfeeding initiation, breastfeeding issues or exclusive breastmilk postpartum. No interaction effects were observed between asthma and maternal comorbidities (body mass index, mental health diagnosis, diabetes) on breastfeeding outcomes.
CONCLUSIONS: Maternal asthma was negatively associated with breastfeeding outcomes in the immediate postpartum period; associations were not explained by perinatal factors or comorbidities. Findings highlight the need for early breastfeeding support for women with asthma.