Association of the Length of the Third Stage of Labor and Blood Loss Following Vaginal Delivery

作者：Rabie Nader Z^*; Ounpraseuth Songthip; Hughes Dawn; Lang Patrick; Wiegel Micah; Magann Everett F

来源：Southern Medical Journal, 2018, 111(3): 178-182.

DOI：10.14423/SMJ.0000000000000778

• blood loss
• hemorrhage
• pregnancy
• third stage of labor

Objectives The length of the third stage of labor is correlated with blood loss following a vaginal delivery. We aimed to accurately measure blood loss following a vaginal delivery and examine the relation between blood loss and length of the third stage of labor.
Methods This was a prospective observational study of singleton pregnancies 24 weeks undergoing a vaginal delivery. Blood loss was meticulously measured and the length of the third stage of labor was recorded.
Results The median blood loss of the 600 women was 125 mL (interquartile range 175) and the median length of the third stage of labor was 5 minutes (interquartile range 4). Total blood loss (P = 0.0263) and length of the third stage of labor (P = 0.0120) were greater in pregnancies 37 weeks versus <37 weeks. Women with a third stage of labor 15 minutes had a significantly greater risk of blood loss >500 mL (relative risk 5.8, 95% confidence interval 8.36-29.88).
Conclusions The median blood loss following a vaginal delivery is 125 mL and the median length of the third stage of labor is 5 minutes. Total blood loss and the length of the third stage of labor are greater in pregnancies >37 weeks. Women with a third stage of labor >15 minutes are 15.8 times more likely to have total blood loss 500 mL. As such, it is prudent to consider manual extraction of the placenta at 15 minutes rather than 30 minutes to minimize the risk of excessive blood loss.

• 出版日期2018-3