Effect of cervical length on second trimester pregnancy termination

Abstract

Aim: To evaluate the value of sonographic measurement of cervical length as a predictor of abortion or delivery within 24 h by misoprostol in second trimester termination of pregnancy (TOP).

Material and methods: One hundred and sixty-three women underwent TOP between 14 and 26 weeks of pregnancy due to various indications. The primary outcome was abortion within 24 h. Cervical length was measured before transvaginal administration of misoprostol. The effects of cervical length, total misoprostol dose, parity, and gestational age at diagnosis on successful TOP were evaluated.

Results: One hundred and sixty-three women were eligible who met the inclusion criteria. TOP occurred in 80.5% of patients within 24 h. Parous women had shorter prolonged induction to expulsion period over 24 h (14.1% vs 28.6%, P = 0.061). Total misoprostol dose and history of abortion were parameters that affected induction to delivery period (P = 0.002 and P = 0.041). Using an optimum cutoff of 36 mm, 58.2% sensitivity and 68.2% specificity were obtained. In addition, positive and negative predictive values were 85.36% and 33.3%, respectively. Pregnant women whose preinduction cervical length was shorter than 36 mm had a shorter induction time and needed a lower total misoprostol dose to achieve TOP than women with a cervical length longer than 36 mm (P = 0.027 and P = 0.011, respectively).

Conclusion: Transvaginal measurement of cervical length before administration of prostaglandin analogue was not correlated with successful TOP within 24 h. It cannot be used as a predictor in light of our findings.