Oxytocin

Oxytocin is an essential lactation hormone released during breastfeeding that causes milk ejection and appears to have calming effect on the mother.[1] Administration of exogenous oxytocin to mothers having difficulty in breastfeeding has not been clearly shown to have a beneficial effect on lactation success or in the treatment of breast engorgement. It might be of benefit with spinal cord injury where the neuronal connection between the breast and hypothalamus have been lost. Effects on the infant are unlikely when oxytocin is given during breastfeeding. Some studies suggest that oxytocin given during labor can negatively affect breastfeeding, possibly by reducing sucking behavior in the newborn in a dose-dependent manner, or by decreasing postpartum oxytocin release although study timing of oxytocin administration and study methodology has varied considerably.[2-20] Another study found no relationship between cumulative oxytocin dosage and breastfeeding success at 1 week postpartum.[18] The effect on breastfeeding might be most important during the initiation of breastfeeding, but may not persist after lactation is established.[21,22] Two studies found that only oxytocin in conjunction with epidural analgesia reduced breastfeeding, but not oxytocin alone.[16,23] Another study found that all rhythmic reflexes, the antigravity reflex, and total primitive neonatal reflexes were inhibited by intrapartum oxytocin administration, unrelated to dose, which could adversely affect breastfeeding.[24] Another small study found that exogenous oxytocin for induction or augmentation of labor was positively associated with higher quality of observed mother-infant bonding,[25] while another study did not find any association with bonding or maternal breastfeeding attitude.[26] Some evidence exists that peripartum oxytocin administration might increase the risk of postpartum depression.[15]