WASHINGTON – The use of mediolateral episiotomy in women undergoing operative vaginal delivery – a common practice in the Netherlands – was associated with a large reduction in the risk of obstetrical anal sphincter injuries, according to an analysis of 10 years of data from the Netherlands Perinatal Registry.
For physicians and other obstetrical providers in the small European country, the findings reinforce current practice of favoring mediolateral episiotomies in operative vaginal deliveries as protection against obstetrical anal sphincter injuries (OASIS) – a risk factor for fecal incontinence, the investigators said.
"In the Netherlands, a mediolateral episiotomy is common practice. ... Our opinion is that the mediolateral episiotomies are causing less morbidity than an anal sphincter rupture would cause," Dr. Jeroen van Bavel reported during a press conference at the scientific meetings of the American Urogynecologic Society (AUGS) and the International Urogynecological Association.
But for physicians here in the United States, the risks are weighed differently. "It’s not that we don’t know that a mediolateral episiotomy decreases the risk of sphincter injury," Dr. Haywood Brown, professor and chair of obstetrics and gynecology at Duke University, Durham, N.C., said in a telephone interview after the conference.
"The problem is, mediolateral incisions are so uncomfortable," said Dr. Brown, who also is chair of the American College of Obstetricians and Gynecologists, District IV.
"They heal poorly, they heal with defects, ... and as a result the patient has more pain related to the mediolateral [episiotomy] than they would have with a third- or fourth-degree tear," he said. "Doing the mediolateral is really not the answer."
The Netherlands Perinatal Registry contains information on 96% of the 1.5 million deliveries that occurred during 2000-2009. Dr. van Bavel, of Amphia Hospital in Breda, the Netherlands, and his coinvestigators focused their analysis on the 170,974 women who had operative vaginal deliveries, comparing the rates of OASIS in women who had mediolateral episiotomies with those who did not.
Among primiparous women who had vacuum deliveries, OASIS occurred in 2.5% of those who had mediolateral episiotomies, compared with 14% who did not. Among multiparous women who had vacuum deliveries, OASIS rates were 2.1% with mediolateral episiotomy versus 7.5% without.
The differences were more striking with forceps deliveries. Anal sphincter injuries occurred in 3.4% versus 26.7% in primiparous women with and without mediolateral episiotomies, respectively. Among multiparous women, the risk of OASIS was 2.6% versus 14.2%.
For primiparous women, the number of mediolateral episiotomies needed to prevent one OASIS was 8 for vacuum delivery and 4 for forceps delivery, according to the analysis. For multiparous women, 18 mediolateral episiotomies were needed to prevent one OASIS for vacuum delivery, and 8 for forceps delivery.
ACOG’s Practice Bulletin No. 71 on episiotomy, which was written in 2006 (Obstet. Gynecol. 2006;107:957-62) and reaffirmed in 2013, states that median episiotomy is associated with higher rates of injury to the anal sphincter and rectum than mediolateral episiotomy (level A evidence), and that mediolateral episiotomy may be preferable in selected cases (level B evidence).
Overall, "restricted use of episiotomy is preferable to routine use of episiotomy," the guidelines say (level A evidence). Postpartum recovery, the guidelines note, is an area of obstetrics that lacks systematic study and analysis.
Dr. Brown said he stands firmly with his belief that mediolateral episiotomy as a routine prophylactic procedure in operative vaginal deliveries cannot be justified. "Having lived through an era of mediolaterals and seeing how long they take to heal, and the discomfort that patients have, I can’t justify it," he said.
"We’ve moved away from episiotomies [in the United States], period," he said. "We’ve moved away from them primarily because of the data showing that midline episiotomies increase the risk of sphincter injury. And the mediolateral episiotomies are just too painful."
The risk of OASIS can be minimized through good delivery technique, he noted.
"The trend here is toward more vacuum deliveries, which have [been shown to be less risky] than forceps deliveries, although its depends on the type of forceps used and the skill of the [obstetrician]," Dr. Brown said. "The challenge we face is that we don’t have enough forceps and vacuum deliveries to easily keep skill levels up."
Dr. Charles W. Nager, president of AUGS and director the urogynecological and reconstructive pelvic surgery division at the University of California, San Diego, said that rates of both episiotomy and operative vaginal delivery have been declining in the United States, and that simultaneously, "there’s been a parallel drop in OASIS."
There also is more training ongoing in U.S. hospitals on repairing third- and fourth-degree obstetric lacerations, he said in an interview at the meeting.