What is the primary function of a Purse-string suture in a surgical context?

• A. Stitch to support uterine prolapse
• B. Suture to prevent closure of the cervix
• C. To heal vaginal wall incision
• D. To correct cervical lacerations

Answer: (B)

The main idea behind a purse-string suture is that it forms a circular stitch around the edge of a circular opening, and when tightened it cinches the tissue together like a drawstring. In the cervix, this technique is used to constrict the cervical canal so it does not open or dilate prematurely. By placing the suture around the cervix and tightening, the surgeon helps keep the cervix closed during the period when an opening would be problematic, such as in procedures aiming to prevent premature dilation. This is why the function described in the correct choice is about preventing the cervix from opening (i.e., keeping it closed) with a circumferential closure mechanism. The other options refer to different surgical goals—supporting prolapse, healing a vaginal incision, or correcting lacerations—not the typical use of a purse-string around the cervix.