McDonald’s cervical cerclage

A cervical cerclage is a surgical procedure in which sutures or synthetic tape is used to reinforce the cervix, and is used in the treatment of cervical incompetence.

McDonald’s cervical cerclage is a type originally described by McDonald in 1957, and is a commonly performed procedure in modern obstetric practice.


Having obtained informed consent and given spinal anaesthesia, patient is placed in lithotomy position, routine cleaning and draping is done, and the bladder is emptied.


The anterior and posterior vaginal walls are retracted with two Sim’s speculum, held in place by the assistant while a purse string suture is applied to the cervix at the junction with the vaginal rugosities. A total of 4 bites are taken at 2, 5, 7 and 10 o’clock positions with a 4-mm Mersilene tape. Bites are avoided at 3 o’clock and 9 o’clock positions in order to prevent bleeding.

The suture is tied anteriorly after tightening so that the cervical canal cannot admit a finger. The ends of the suture are left long (2-3cm) to allow for easy removal.


After the procedure, the patient is transferred to the ward, placed on strict bed rest and commenced on oral antibiotics, with or without tocolytics. Patient is counselled on the need for pelvic rest and discharged home after a few days on admission.

Demerits of McDonald’s cervical cerclage

  1. It is not anatomical. The purse string is placed at the junction of the cervix with the vaginal rugosities which is not at the level of the internal os.
  2. The exposed vaginal suture may predispose to vaginitis.