Plasma renin activity after birth and in the early newborn period.
Plasma renin activity (PRA) was studied during delivery in umbilical cord venous blood and serially in the first 48 hours of life. PRA after cesarean section without labor, 15.2 +/- 2.3 ng/ml/hr (mean and SEM), was less than after cesarean section with labor, 44.1 +/- 8.9 (P less than .02), and vaginal delivery, 34.7 +/- 4.3 (P less than .05). PRA decreased during the first 30 minutes after vaginal delivery from 34.7 +/- 4.3 ng/ml/hr to 19.3 +/- 3.5 (P less than .01); PRA subsequently increased by four hours of life to 38.6 +/- 6.7 mg/ml/hr (P less than .05) and remained elevated throughout the 48-hour study period. These data show that PRA is stimulated during labor, decreases postnatally, and is again restimulated in the early newborn period.
D002585:Cesarean Section; D036861:Delivery, Obstetric; D005260:Female; D005312:Fetal Blood; D006801:Humans; D007231:Infant, Newborn; D007743:Labor, Obstetric; D011247:Pregnancy; D012083:Renin / Q000097:blood*; D012964:Sodium / Q000097:blood; D013997:Time Factors
D012964:Sodium; D012083:Renin