Witch's milk

Witch's milk or neonatal milk is milk secreted from the breasts of some newborn human infants of either sex.^[1] Production of neonatal milk by infants usually resolves itself and does not require treatment unless it is caused by an underlying condition or medications.^[2] It is thought to be caused by the exposure to an elevated level of estrogen to infants during pregnancy^[2] or decreased exposure of estrogen to infants after birth.^[3] Its production also may be caused by certain medications.^[4][5] The composition of neonatal milk is similar to maternal milk for most of their components except for fats and one type of antibody.^[6][7]

Neonatal milk production occurs in about 6% of newborns with age from 0 to 12 weeks. Within the age range, infants age 0 to 2 weeks were found to have the highest occurrence. Compared to those who did not have neonatal milk production, infants who did had larger breast nodules.^[8] Pre-term infants under the gestational age of 34 weeks did not secrete milk as observed in one study.^[9] Complications such as mastitis and abscesses are associated with breast massage of the neonate's breast.^[10] Squeezing of neonate's breast could also result in an infection.^[3] Blood from the nipples is nearly always benign and frequently associated with duct ectasia; it should only be investigated when it is unilateral.^[11]

The name witch's milk originates from ancient folklore^[12] and is associated with religious and cultural interpretations.^[13][14]