Cervical incompetence concerns less than 1% of the obstetrical population [1,2]. It is ill-defined as an anatomical or functional cervical defect that prevents a woman from carrying a pregnancy to term, resulting in recurrent late miscarriages and premature deliveries if untreated [1,3]. It is often characterized by a painless cervical dilation, in the second trimester or at the beginning of the third trimester of pregnancy, leading to a hernia of the membranes in the vagina and then to the loss of the pregnancy, often in a sudden and unpredictable way. Although there are several diagnostic tests (hysterography, cervical calibration with Hegar dilators or Foley catheter, etc.) [4], cervical insufficiency is difficult to diagnose as definition of the disease is unclear. In most cases, it is based on the history of repeated pregnancy losses, after ruling out other causes.

Described for the first time by Shirodkar in 1955 [5] and simplified by McDonald [6] and Hervet [7] in 1957 and 1959, cervical cerclage is considered an effective treatment for some patients with cervical insufficiency [8]. It is a simple procedure, which consists in reinforcing the cervix with a non-absorbable thread or a strip to prevent its early dilation during pregnancy and reduce the preterm birth risk [9]. This transvaginal cerclage is placed during pregnancy and can be removed close to term to allow a vaginal delivery.

In rare cases, cervical cerclage is ineffective or not feasible, so the cerclage must be placed higher. In 1965, Benson and Durfee [10] performed a cervicoisthmic cerclage by laparotomy. It consists of placing a strip of Mersilene medial to the ascending and descending branches of the uterine artery, at cervico-corporeal junction. This cerclage is intended to be permanent and requires a cesarian delivery. However, the morbidity related to the abdominal approach precludes its further development [10], [11], [12]. Cervicoisthmic cerclage was then described in 1998 by laparoscopy, allowing a reduction in maternal morbidity [13], [14], [15], [16]. In 2001, Golfier et al. first described the transvaginal cervicoisthmic cerclage, allowing to locate the cerclage as high on the isthmus as with the abdominal route [17]. This new technique, performed with non-absorbable suture, after performing a paracervical dissection and opening Douglas’ pouch, seemed to be as effective as the abdominal route on neonatal survival [18].

The guidelines for performing cervicoisthmic cerclage concern a small number of patients, having a history of cervical insufficiency with a previous failed transvaginal cerclage, or a significant cervical abnormality [8]. Therefore, the literature on this subject is poor.

The main objective of this study is to evaluate the effectiveness of cervicoisthmic cerclage in patients with cervical incompetence, by comparing live births rates before and after cervicoisthmic cerclage, according to a before-after study design, in patients treated in the 3 university hospitals in Lyon, France, over the last ten years.