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Jan. 6, 2000 (New York) -- Episiotomy, one of the most common medical procedures performed on women, can cause long-lasting injury to the rectum, according to study in the Jan. 8 issue of the British Medical Journal. Women who had an episiotomy -- the surgical cutting of the perineal tissue between the vagina and anus to widen the birth canal -- during labor reported a significantly higher inability to control bowel movements and gas, a condition known as anal incontinence, after giving birth than women who did not require an episiotomy or whose perineum tore naturally during labor.
Although major reasons for performing an episiotomy include preventing severe tearing of the perineum that may be difficult to heal and protecting the anal sphincter muscle from damage, the study of more than 600 women calls that theory into question, according to lead study author Lisa B. Signorello, MD.
"There have been a number of studies over the past two decades that have looked at all sorts of outcomes such as pain, healing, sexual functioning. Our study is maybe the first to look at anal incontinence, but it just adds to the literature showing that there really does not seem to be a widespread benefit to using episiotomy routinely," says Signorello, an epidemiologist at the International Epidemiology Institute, Rockville, Md.
The study compared characteristics of 209 women who received an episiotomy, 206 women who experienced spontaneous tearing of the perineum, and 211 women who did not sustain injury to the perineum during labor.
Women who had episiotomies had a five times higher rate of uncontrolled bowel movements three months after giving birth compared with the group with no perineum injury, which decreased to about a four times higher rate six months after birth. Compared with the group with spontaneous tearing of the perineum, uncontrolled bowel movements were three times higher at three months and six months after birth. The rate of uncontrolled gas was twice as high at three and six months after birth in the episiotomy group compared with those who had spontaneous tears.
Some studies had implicated both episiotomy and the use of forceps during delivery, or instrumental birth, in causing the damage to the anal sphincter that leads to the uncontrolled bowel movements and gas, but the new study was able to rule out forceps as well as any other factors.
"It's been a difficulty in previous studies because many did not have a large enough sample size to separate out women who had an instrumental birth from those who didn't," Signorello tells WebMD. "But in our study the results are still strong and significant after you exclude anybody who had an instrumental birth or who had any labor complication. There was nothing else going on in these women except for the episiotomy."
In the U.S., episiotomy is performed in about 60% of live births, but that figure varies from doctor to doctor and hospital to hospital. Signorello says some hospitals still have episiotomy rates as high as 90% or more for first-time deliveries but says it is clear that many physicians are moving toward reserving an episiotomy for high-risk labor, such as when the baby is in distress and must be delivered in a hurry.
"Episiotomy is an example of medical technology that perhaps wasn't tested as well as it should have been before it was used in a widespread manner," Signorello says. "If you really look at the research, there's just no scientific basis for using this procedure as standard practice. Certainly, we don't give a C-section to every woman in labor, and this is the same sort of situation."
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