Odds ratio of 3.5: prepregnancy LEEP may predispose to preterm delivery.(News)

EDMONTON, ALTA -- Women who underwent a loop electrosurgical excision procedure before becoming pregnant were more than three times as likely as were matched controls to deliver prematurely in a retrospective cohort study. Dr. Sheri-Lee Samson reported.

The study tracked all patients who had a loop electrosurgical excision procedure (LEEP) in Halifax County, Nova Scotia, Canada, between 1992 and 1999.

Dr. Samson and her associates at Dalhousie University in Halifax compared singleton deliveries of 571 patients who had a history of LEEP in the county with 571 residents matched for age, parity, smoking history, and the year of delivery.

Patients who had LEEP were significantly more likely to deliver before 37 weeks' gestation (7.9% vs. 2.5%, with an odds ratio of 3.5). Dr. Samson said at the annual meeting of the Society of Obstetricians and Gynaecologists of Canada.

"Treatment with LEEP significantly increases preterm delivery at less than 37 weeks in otherwise low-risk women," said Dr. Samson, who calculated that for every 19 LEEP procedures, one patient could be expected to deliver prematurely.

Women who had undergone LEEP also were more likely to have low-birth-weight babies (5% vs. 2%).

More patients with a LEEP history delivered at less than 34 weeks, but the difference was not statistically significant because the study ...