Stress during labor and delivery and early lactation performance

Area of Science:

• Reproductive Endocrinology
• Maternal-Fetal Medicine
• Lactation Physiology

Background:

• Labor and delivery stress varies between mothers and fetuses, differing between first-time (primiparous) and experienced (multiparous) mothers.
• Lactogenesis, the onset of copious milk production, is a critical aspect of postpartum maternal-infant bonding and infant nutrition.

Purpose of the Study:

• To investigate the relationship between the birth experience and lactation performance in postpartum women.
• To identify risk factors associated with delayed lactogenesis.

Main Methods:

• Measured stress hormones in maternal and cord blood during pregnancy, parturition, and lactation.
• Collected milk samples and recorded breastfeeding frequency for the first two weeks postpartum.
• Assessed lactogenesis using breast fullness, 24-hour milk volume, milk lactose concentration, and casein appearance.

Main Results:

• Primiparous mothers experienced delayed breast fullness and lower day 5 milk volume compared to multiparous mothers.
• Maternal and fetal stress markers (cord glucose, maternal exhaustion) during labor were linked to delayed breast fullness and casein appearance.
• Higher maternal exhaustion scores correlated with lower day 5 milk volume; prolonged labor independently predicted delayed casein appearance.

Conclusions:

• Primiparity, prolonged labor, and elevated maternal/fetal stress during birth are identified as risk factors for delayed lactogenesis.
• Elevated cord glucose concentrations are associated with delayed onset of milk production.
• Pregnancy weight gain was inversely related to milk lactose concentration.