HYPERGASTRINEMIA OF NEWBORNS AND INFANTS DURING BREAST-FEEDING

Objective: We determined gastrin concentrations in newborns and their mothers both before and during lactation. Methods: Twenty-five women w ho had uncomplicated pregnancies with normal vaginal delivery of healt hy infants at term participated in the study. Twelve preterm neonates with low birth weight (LBW) were also studied. Gastrin levels were det ermined by radioimmunoassay in amniotic fluid and in serum of both the neonates and their mothers at birth and during breast-feeding. Serum levels of gastrin and prolactin (PRL) were measured in the mothers bef ore and after tactile self-stimulation of the breast. Results: In norm al newborns, gastrin levels in cord sera were significantly higher tha n levels in maternal blood and amniotic fluid at birth. However, gastr in cord sera in LBW newborns was lower than in the normal neonates. Nu rsing resulted in an increment of serum gastrin levels in the infants and mothers; this rise was similar in the 3 postpartum weeks tested. T actile stimulus of the mother's nipple resulted in increases of both g astrin and PRL. Conclusions: Newborns at term show significantly highe r gastrin levels than do LBW neonates, which may indicate differences in development of the gastrointestinal system. Breast-feeding induced gastrin secretion in both mothers and infants, confirming the presence of an active vagal reflex. In addition, tactile stimulation of the ni pple increased gastrin and PRL levels in the mothers. Our data suggest that LBW neonates have deficient production of gastrin, which in turn may indicate an undeveloped gastrointestinal system. An early enteral feeding triggers the postnatal increase in concentrations of gut horm ones.