Background: The aim of this study was to critically review the evidence base on maternal alcohol use during lactation to ascertain its effect on the breastfed infant and also the effect on the hormonal regulation of lactation. The aim of this was to synthesize the research findings into clinically useful recommendations regarding the consumption of alcohol in lactation for health professionals (particularly GPs, Midwives, Health Visitors and Breastfeeding Counsellors) to be able to support these women to achieve optimal breastfeeding outcomes.
Methods: Healthcare databases Medline, Cinahl, British Nursing Index and PsycINFO were searched for articles published from 1988 to present. Earlier human studies which were deemed seminal and also animal studies were included due to the limited amount of contemporary human studies found. These articles underwent subsequent critical appraisal.
Results: The effects of alcohol on offspring’s growth, development (mental and gross motor), behaviour, sleep and blood alcohol levels were investigated and it was found that although alcohol does pass to the infant via the breast milk, only sleep and behaviour were found to be significantly affected. A large body of animal and human experimental studies demonstrated that the hormonal milieu of lactation was significantly disrupted by alcohol consumption with maternal doses as little as 0.3g/kg body weight. Ingestion of alcohol consistently inhibited the milk-ejection reflex by inhibiting the release of oxytocin causing less milk to be available to the infant. The release of prolactin was also disturbed but this did not have a profound effect on long-term milk synthesis.
Conclusions: As maternal alcohol consumption can profoundly adversely affect the hormonal regulation of lactation and alcohol passing to the infant via the breast milk causes sleep and behavioural problems; it is imperative clear guidance is available to health professionals so that they may advise new mothers in making informed choices about alcohol use whilst breastfeeding. This increased awareness may aid early problem-recognition thus ameliorating effects experienced by the infant and contribute to increased duration of breastfeeding. Recommendations are stated in this report.