Background: Breastfeeding is the safest and best method for nurturing infant growth and health. While the harmful effects of alcohol during pregnancy are well-established, the consequences of alcohol intake during lactation have been far less examined. The effects of alcohol intake with large amounts noted on the infant include drowsiness, diaphoresis, deep sleep, weakness, decrease in linear growth, abnormal weight gain. Daily consumption of 1 g/Kg alcohol decreases milk ejection reflex. The aim of the present study is to review the literature on the physiological process and hormonal control of lactogenesis, the milk ejection reflex (let down), and the effect of alcohol on these processes in both short and long term.
Methods: A systematic literature review was conducted using the electronic databases PubMed, Drugs and Lactation Database (LactMed) and ISI Web of Knowledge from 1999 to 2014. The search terms were "breastfeeding", "lactation" and "alcohol".
Results: Alcohol levels in the breast milk are similar to the blood alcohol levels of the mother at the time of feeding. A breastfeeding infant is exposed to a very small amount of the alcohol the mother drinks, but infants detoxify alcohol in their first weeks of life at half the rate of adults. Alcohol is not stored in the breast milk and passed to the infant at a later feeding. A single exposure of alcohol from breast milk may have a mildly sedating effect or alter the odor or taste of the breast milk. It has been recommended to avoid breastfeeding for about 2 hours after drinking one alcoholic beverage.
Excessive use of alcohol can affect milk flow in lactating mothers. Adverse effects on nursing infants include: impaired motor development, changes in sleep patterns, decrease in milk intake, risk of hypoglycemia and slightly reduce milk production
Conclusion: Exposure to alcohol in mothers' milk disrupted the infant's sleep-wake pattern and motor development in ways that are contrary to the folklore. Scientific evidences such as that discussed above should not frighten women away from breastfeeding. Clear guidelines for alcohol consumption are required for lactating women and health professionals to guide breastfeeding mothers to make educated choices regarding alcohol intake during this critical period of infant development.