Ultrasound-predicated versus history-predicated cerclage in women at risk of cervical insufficiency: a systematic review.

The aim of this systematic review was to compare pregnancy outcomes and cerclage-related complications of ultrasound-predicated versus history-predicated cerclage in patients at risk of cervical insufficiency due to a history of preterm delivery (PTD). A structured search was performed in PubMed, Embase, and the Cochrane Library to identify potentially relevant articles from January 1980 through July 2007. Studies were included if ultrasound-predicated cerclage was compared to history-predicated cerclage in women with a singleton gestation and a history of PTD. The PubMed, Embase, and Cochrane search yielded 537, 643, and 42 articles, respectively. In addition, 1194 "Related articles" (PubMed) and 87 "Cited in/cited by" (ISI-WOS) from all potentially relevant articles were assessed. After critical evaluation for relevance and quality, 6 articles remained. Five of the 6 included studies showed no differences in pregnancy outcome (PTD or pregnancy loss <24 weeks) between the ultrasound-predicated and the history-predicated cerclage groups. In 1 prospective cohort study, PTD below 30 weeks was significantly lower in the ultrasound group. The included studies showed that in the ultrasound group, 40% to 68% of the patients did not require cerclage. The majority of studies provided insufficient data to draw conclusions regarding cerclage-related complications. In conclusion, using ultrasound to identify women at risk of cervical insufficiency because of a history of PTD reduces cerclage rates and results in similar pregnancy outcomes as cerclage placement on the basis of history alone.