Considered the most common method of pain relief for women who are about to give birth, epidural anesthesia is requested in over 50 percent of delivery rooms in the United States. A recent study out of the University of California, San Francisco (UCSF), however, revealed that women who receive a shot of an epidural before delivering their child increase the amount of time they are in labor by two hours.

According to the Centers for Disease Control and Prevention, around 61 percent of women who delivered a single child in 2008 used either an epidural or spinal anesthesia to relieve their pain. Women were more likely to use an epidural if they were educated in maternal or prenatal care and less likely to use one as their age progressed. The likelihood of epidural use also rose in the event of vaginal forceps delivery by 84 percent and vacuum extraction by 77 percent, compared with spontaneous vaginal delivery at 60 percent.

Lead researcher, Dr. Yvonne Cheng, and her colleagues from the university’s maternal-fetal medicine department analyzed data from 42,268 women who delivered their child vaginally at UCSF between 1976 and 2008. Around half of the women observed in this study required an epidural to help with their labor pains while the other half did not. The average length of the second stage of labor was compared in women who delivered their child with an epidural and without an epidural.

Among women who were delivering their first child, the second stage of child birth took, on average, 3.3 hours for those who received an epidural and 5.6 hours — a two-hour and 19-minute difference — for those who did not receive an epidural. Women who had given birth before took an hour and 21 minutes to deliver their child without an epidural and four hours and 15 minutes with an epidural — a two-hour and 54-minute difference.

"The effect of epidural can be longer than we think and as long as the baby looks good and the women are making progress, we don't necessarily have to intervene (and perform a Cesarean section) based on the passage of time," Cheng told Reuters. "All the experts in the field should get together to look at the evidence that's out there and come up with informed definitions."

The American Pregnancy Association has gathered a list of potential risks and benefits involved with using an epidural during vaginal childbirth. For example, women who receive an epidural to soothe labor pains are generally more alert during the delivery, deal with less exhaustion, irritability and fatigue, and rest more during a prolonged labor time. On the other hand, women who receive an epidural also run the risk of experiencing a sudden drop in blood pressure, soreness in the area where the needle was inserted, and could make pushing more difficult. Pregnant women should seek the advice of their doctor before making any decision involved with their delivery.

Source: Schaffer B, Nicholson J, Caughey A, Cheng Y. Second Stage of Labor and Epidural Use: A Larger Effect Than Previously Suggested. Obstetrics and Gynaecology. 2014.