RANCHO MIRAGE, CALIF. — Genital trauma during delivery was common but did not lead to postpartum urinary incontinence in a prospective study of 455 midwifery patients with low-risk pregnancies.
The findings of the study counter a common reason that is often cited for performing episiotomies: to prevent anterior genital trauma in hopes of avoiding future incontinence.
As episiotomy rates decreased from 55% of deliveries in 1991 to 29% in 2001, the rate of anterior lacerations increased, leading investigators in the current study to analyze whether the increase in lacerations was associated with urinary incontinence.
Only 20% of the 455 women had no lacerations after delivery. An additional 35% had anterior lacerations to the clitoral, labial, or periurethral tissues; 18% developed posterior (perineal) lacerations, and 25% had both anterior and posterior trauma, Rebecca Rogers, M.D., said at the annual meeting of the Society of Gynecologic Surgeons.
The remaining 2% of women were excluded from analysis because their vaginal lacerations did not extend to external genitalia. Only two of these nine patients required sutures.
Most of the trauma included in the analyses was minor. Only 1% of patients developed a posterior third- or fourth-degree laceration, according to Dr. Rogers of the University of New Mexico, Albuquerque.
Urinary incontinence was reported by 27% of women 6 weeks after delivery and by 29% 3 months after delivery. These women answered “yes” to the question, “Since the birth of your baby, have you leaked urine when you did not mean to?”
Fewer women, however, felt that the incontinence significantly affected their social functioning. Postpartum, 16% of women at 6 weeks and 13% at 3 months scored greater than 0 on the Incontinence Impact Questionnaire-7 (IIQ-7), which defined significant impact.
The urinary incontinence was not associated with the presence of genital trauma or any of a number of other factors analyzed. On the contrary, women with anterior lacerations were less likely to have urinary incontinence at 3 months post partum, compared with all other women combined.
“This is a little surprising to us because, if anything, we thought we would find that anterior trauma was linked to complaints of incontinence,” Dr. Rogers said. “Isolated anterior trauma may serve as a marker for preservation of the continence mechanism in some way that I can't really explain at this point.”
In formal commentary after Dr. Rogers' presentation, Charles Nager, M.D., said, “The important part of this study is that it dispels a commonly held belief by many obstetricians that episiotomy, which does reduce the risk of anterior genital tract trauma, can be justified because it helps prevent incontinence.”
The results are consistent with a Cochrane Review of other studies on episiotomy at vaginal birth, which found that a “restricted episiotomy” protocol increased the relative risk of anterior trauma by 79%, compared with routine episiotomy—but this difference reportedly did not increase the risk for urinary incontinence or dyspareunia, said Dr. Nager of the University of California, San Diego.
“The authors [of the current study] should be commended for a well-done, prospective, clinically relevant and clinically important study,” he said.
Participants in the study agreed to mapping of genital trauma at birth and two postpartum assessments of perineal anatomy, urinary continence, and incontinence-related social functioning.
The study excluded women who underwent episiotomy or operative delivery, he said.
The participants were an average 25 years of age, and 40% were nulliparous. For delivery, 41% had epidural anesthesia and 23% received oxytocin.
The investigators will analyze data on sexual function and anal incontinence, Dr. Rogers said. In a preliminary review, genital trauma did not seem to be linked to either of these.
“Anterior genital tract trauma is not something that we need to be extremely concerned about preventing,” Dr. Rogers explained.