Oxytocin concentrations during the neonatal period

Area of Science:

• Neonatal physiology
• Endocrinology
• Perinatal medicine

Background:

• Oxytocin plays a crucial role in maternal and infant bonding and physiological regulation.
• Understanding oxytocin dynamics in newborns is essential for assessing developmental and physiological processes.

Purpose of the Study:

• To investigate plasma oxytocin levels in umbilical cord blood and peripheral circulation of newborns.
• To compare oxytocin concentrations between infants delivered via cesarean section and those born after labor.
• To examine the persistence of elevated oxytocin levels in neonates and its presence in breast milk.

Main Methods:

• Measurement of plasma oxytocin concentrations in umbilical artery (UA) and umbilical vein (UV) blood.
• Serial sampling of peripheral venous blood from infants up to 4 days postpartum.
• Analysis of oxytocin levels in breast milk from lactating mothers.

Main Results:

• Umbilical artery oxytocin levels were significantly higher than umbilical venous levels in infants delivered by cesarean section without labor.
• Plasma oxytocin levels decreased rapidly from UA to peripheral venous blood within 30 minutes.
• Elevated plasma oxytocin levels persisted in both breast-fed and formula-fed infants throughout the 4-day study period, exceeding adult basal levels.
• Breast milk contained a mean oxytocin concentration of 10.0 +/- mu U/ml in mothers 2-4 days postpartum.

Conclusions:

• Neonatal oxytocin secretion is stimulated during the perinatal period, with distinct patterns observed based on delivery mode.
• Oxytocin levels remain elevated in infants post-birth, suggesting a continued physiological role.
• The presence of oxytocin in breast milk highlights its potential importance in the early postnatal period and infant development.