Nearly 70 percent of mothers require perineal sutures because of tears or episiotomy during vaginal birth. For most of these women, perineal discomfort persists, and about 20 percent report long-term discomfort and dyspareunia. Factors linked to post-repair perineal pain include the extent of damage, the technique of repair, the experience and skill of the operator, and the type of suturing material selected. Kettle and colleagues compared continuous versus interrupted suture techniques and standard suture material (polyglactin 910) versus rapidly absorbed (polyglactin 910) suture material in women delivering at an English regional hospital.

All mothers who sustained second-degree perineal tears or episiotomy during spontaneous vaginal delivery were eligible for the study unless there was substantial perineal trauma, evidence of perineal pathology, or history of human immunodeficiency virus or hepatitis B virus infection. Mothers younger than 16 years of age, those who had an instrumental vaginal delivery, those who had given birth to a stillborn child or a child with extensive congenital defects, and those who could not read, write, or understand English also were excluded.

An extensive staff-training program was undertaken during the nine months before the study, including audit of practice with feedback for all midwives. The 1,542 mothers were randomly assigned to different combinations of materials and methods. Suturing was done by supervised, trained midwives to ensure minimum deviation from protocols. Although the two suture materials appeared similar, the technique could not be blinded. Both the midwife and the patient completed questionnaires two and 10 days after the birth. Mothers also completed questionnaires three and 12 months after delivery.

The groups were comparable in all important respects. Adherence to the study protocol was good. The continuous-repair technique was associated with significantly less pain at 10 days than the interrupted method, and this advantage persisted for at least 12 months. Pain also was reduced when the repair was performed by a more experienced midwife. Mothers who received the continuous-repair method were less likely to require suture removal or to experience wound gaping. Patient satisfaction was higher with the continuous-suturing technique, and 59 percent of mothers in this group reported feeling back to normal within three months of delivery, compared with 48 percent of those who received interrupted sutures.

The choice of suture material did not have a significant effect on pain at day 10 or dyspareunia at three months. Significantly fewer mothers (2.9 percent compared with 12.7 percent) required suture removal when the more rapidly absorbed material was used. For other outcomes, the results with the two suture materials were mixed.

The authors conclude that the continuous-repair technique can have a significant effect on pain after childbirth and results in about one less patient with pain for every six for whom the technique is used. They also advocate using the more rapidly absorbed suture material because of the reduced need for suture removal.