Aetna considers transabdominal cerclage medically necessary for the treatment of an incompetent cervix for any of the following conditions:

1. Deep traumatized cervix; or
2. Previous failed cervical (transvaginal) cerclages; or
3. Shortened (less than 2.5 cm) or amputated cervix.

Aetna considers transabdominal cerclage experimental and investigational for all other indications because of insufficient evidence of effectiveness.

Note: A history consistent with incompetent cervix must be documented to establish the medical necessity of this procedure. This includes a history of mid-trimester pregnancy loss that is associated with painless cervical dilatation without evidence of uterine activity.

Incompetent cervix is a significant cause of second-trimester pregnancy loss.  It is portrayed by gradual, painless dilation of the cervix in the second or third trimester with bulging and rupture of the membranes and subsequent expulsion of a fetus too immature to survive.

Cervical incompetence may be due to previous obstetric or gynecological trauma or a congenital weakness of the cervix (NICE, 2007). The condition is usually diagnosed after one or more late second trimester or early third trimester pregnancy losses, and after other causes have been excluded.

The role of cervical cerclage in the prevention of miscarriage due to cervical incompetence is well established yet remains controversial.  The most commonly employed techniques are performed vaginally and are designed to reinforce the cervix at the level of the internal os.  This involves placing a stitch of strong thread or tape around the cervix, via the vagina, and tightening it to keep the cervix closed. The procedure is typically performed at the end of the first trimester or the beginning of the second trimester, and the stitch is usually removed at around 37 weeks’ gestation (NICE, 2007).

If there is insufficient cervical tissue to allow placement of a cerclage vaginally, a transabdominal approach (either open or laparoscopic) is sometimes used.  With this procedure, an encircling suture is placed above the cardinal and uterosacral ligaments.  Transabdominal cerclage is not frequently performed and is only indicated for those patients with previous failed cervical cerclages, shortened or amputated cervix, and/or deep traumatized cervix.  This procedure should only be performed by physicians with special training and expertise in this procedure.

The clinical value of pre-pregnancy cerclage has not been firmly established.  In a meta-analysis, Drakeley and colleagues (2003) stated that the effectiveness of prophylactic cerclage in preventing preterm delivery in women at low or medium risk for second-trimester pregnancy loss has not been proven.  The role of cerclage in women whose ultrasound reveals short cervix remains uncertain.  Shennan and Jones (2004) stated that elective cerclage is only effective in a minority of women, and the evidence to support its use is limited.  It is currently being evaluated whether indicated cerclage, dictated by ultrasound findings, is beneficial.

The Royal College of Obstetricians and Gynaecologists' guideline on the investigation and treatment of couples with recurrent miscarriage (2003) did not mention the use of pre-pregnancy cerclage.  Furthermore, the American College of Obstetricians and Gynecologists' guideline on cervical insufficiency (2003) stated that elective cerclage can be considered in patients with a history of 3 or more unexplained mid-trimester pregnancy losses or preterm deliveries.  Moreover, cerclage should be performed at 13 to 16 weeks gestation after ultrasound evaluation has shown the presence of a live fetus with no apparent anomalies.

Guidance from the National Institute for Health and Clinical Excellence (2007) stated that the evidence on the safety and efficacy of laparoscopic cerclage for prevention of recurrent pregnancy loss due to cervical incompetence is limited, and therefore this procedure should not be used without special arrangements for consent and for audit or research. The Specialist Advisers to NICe considered this procedure to be novel and expressed uncertainty about its efficacy. They listed key efficacy outcomes of laparoscopic cerclage as live birth rate, ‘take-home baby’ rate, prolongation of pregnancy, reduction in perioperative morbidity and perinatal morbidity, operating times and blood loss. The NICE guidance noted that It was noted that there is uncertainty about the efficacy of all cervical cerclage techniques as a treatment for recurrent loss of pregnancy due to cervical incompetence. The NICE The Committee noted specific concerns about performing the procedure in women who are not pregnant. These include the difficulty in defining the internal os for correct placement of the suture, and ensuring that the suture is not tied in such a way that there is a risk of it cutting through the cervix during subsequent pregnancy.