Cervical sonography in pregnant women with a prior cone biopsy or loop electrosurgical excision procedure

Objectives To determine if pregnant women with a prior cone biopsy or loop electrosurgical excision procedure (LEEP) have a shorter midtrimester cervical length than do matched controls without a history of cervical surgery. Methods Eighty-five pregnant women with a singleton gestation and previous cone biopsy or LEEP and 85 controls matched by age (+/- 5 years), race, gestational age (+/- 2 weeks), and number of prior vaginal deliveries underwent a single transvaginal cervical sonographic scan at 15-22 weeks' gestation. No patient had a cerclage in either group. Results Mean cervical length was significantly shorter in the cone biopsy/LEEP group (3.3 vs. 3.9 cm, P < 0.001), with no significant difference in the proportion of cervical lengths less than 2.5 cm (5.9 vs. 2.4%). Gestational age at delivery was slightly but significantly lower in the cone biopsy/LEEP group (38.1 vs. 39.1 weeks, P = 0.005) than in the control group, with a higher proportion of women delivering late preterm and very preterm in the cone biopsy/LEEP group. However, no woman with a prior cone biopsy/LEEP experienced a midtrimester loss suggestive of cervical insufficiency, and no patient with a cervical length less than 2.5 cm delivered before 34 weeks' gestation. Conclusions Midtrimester cervical length in women with a previous cone biopsy or LEEP is significantly shorter than in those without prior cervical surgery. Based on the low frequency of a short cervix or midtrimester loss in women with prior excisional surgery, the routine use of midtrimester cervical sonography in such women is not supported. Copyright (C) 2010 ISUOG. Published by John Wiley & Sons, Ltd.