ABSTRACT
Aims At the time of publication, there was limited evidence on outcomes of breastfeeding mother-child dyads on breastfeeding after COVID-19 vaccination. The aim of this study is to systematically quantify the incidence of local and systemic adverse events in lactating women and their children to allow clinicians to appropriately counsel lactating women on the risks-benefit ratio of WHO-approved COVID-19 vaccinations. Methods A cross sectional survey was conducted from 14th August 2021 to 5th January 2022 in Singapore and Malaysia. Data including demographic information, maternal and child symptoms, and vaccine history were collected through an online questionnaire. The survey was distributed online through social media and advertisements. Women more than 21 years of age who received at least one dose of the WHOapproved COVID-19 vaccines Pfizer-BioNTech, Moderna, AstraZeneca, Sinovac while pregnant or lactating were eligible for the survey. Results Responses of 2043 breastfeeding mothers were analysed. 1747 mothers received mRNA vaccines and 296 mothers received non-mRNA vaccines. Overall in terms of maternal reactogenicity, 79.3% and 79.5% of mothers reported any reactions to the first and second dose respectively, primarily local reactions (64.1% dose 1, 57.0% dose 2). 91.8% of mothers breastfed their child uninterrupted after receiving the COVID-19 vaccination. 89.2% of breastfed infants had no symptoms reported following maternal COVID-19 vaccination. More than half (54.8%) of lactating respondents reported no change in milk supply or production. Among those experiencing changes in lactation, symptoms lasted for an average of 4.2 +/- 6.9 days. Conclusion Our findings suggest that the vaccine resulted in minimal disruption of lactation or adverse impact on the breastfed child in mothers receiving COVID-19 vaccination. Breastfeeding mothers may experience a change in breast milk supply when receiving COVID-19 vaccinations, which may be mitigated by proactive measures to ensure adequate rest and hydration. There is minimal severe reactogenicity with COVID-19 vaccination in lactating motherchild dyads.