Synthetic sutures appear to cause less pain than natural “catgut” sutures in women who receive stitches after a vaginal birth, according to a new review of studies.
Researchers led by Christine Kettle, Ph.D., of the University Hospital of North Staffordshire, in England, found that women stitched with synthetic sutures had less pain in the three days after giving birth, and took fewer painkillers over the next 10 days.
However, stitching technique — and the skill of the person doing the stitching — might have also influenced the amount of pain the new mothers felt, the reviewers concluded.
The review appears in the current issue of The Cochrane Library, a publication of The Cochrane Collaboration, an international organization that evaluates research in all aspects of health care. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing trials on a topic.
About 70 percent of women who give birth vaginally suffer damage to the perineum — the muscles and skin between the vagina and the anus — that requires stitches. The perineum might tear during delivery, or a physician or midwife might make a small incision to the area called an episiotomy to enlarge the vagina during birth.
Pain at the sutured tear or cut “can be distressing for the new mother when she is trying to cope with hormonal changes and the demands of her baby, and it can have a long-term effect on her sexual relationship,” Kettle said.
The body absorbs most sutures eventually. However, some sutures break down before the wound is closed and a doctor or midwife must remove others, leading to further pain and delayed healing.
To find out whether the type of suture material might contribute to these complications, the Cochrane reviewers analyzed 18 studies of perineal stitching that included more than 10,000 women. Most of the women had either an episiotomy or a tear that involved the perineal skin and muscles.
Although the review found that catgut sutures were more painful than synthetic stitches over the short-term, most women in developed countries already receive synthetic stitches, the reviewers noted.
When Kettle and colleagues compared standard synthetic sutures to a rapidly absorbing synthetic stitch, they found that a physician or midwife needed to remove standard sutures more often. “This is an important finding,” she said, “as women report that having perineal sutures removed is an extremely unpleasant procedure.”
Different studies used different suturing techniques, such as stitching with a continuous thread or a series of “interrupted, tied-off stitches,” said Kettle. She noted that some “operators used materials and techniques that were unfamiliar to them.”
She noted that such differences could “also affect the amount of pain and the way perineal wounds heal.”
Kettle was the lead author on one of the studies analyzed for the Cochrane review and a U.K. suture manufacturer provided a small amount of funding toward the salary of a part-time clerk who worked on the study.
Kettle C, Dowswell T, Ismail KMK. Absorbable suture materials for primary repair of episiotomy and second degree tears. The Cochrane Database of Systematic Reviews 2010, Issue 6.