Background: To study maternal and fetal plasma levels of catecholamines (CA) during pregnancy and delivery, especially changes in CA levels during fetal distress and conditions of different modes of delivery.
Methods: Maternal and fetal plasma NE, E and DA levels were determined by high performance liquid chromatography (HPLC) for 16 non-pregnant women, 19 cases of early pregnancy, 17 cases of mid pregnancy, late pregnancy, spontaneous vaginal delivery and 53 cases of cesarean section.
Results: Plasma NE and DA levels decreased gradually with the advance of gestational weeks, and levels of plasma NE were significantly lower than those of non-pregnant women (P < 0.05). The levels of plasma CA in patients who had elective cesarean section were significantly lower than those who had vaginal delivery and emergency cesarean section (P < 0.01). However, CA levels of the cord artery in the vaginal delivery group were significantly higher than those in the cesarean section group (P < 0.01).
Conclusion: Vaginal delivery is better than cesarean section for the newborn. If cesarean section is necessary, it is best for the newborn after onset of labor.