Cervical length and risk of antepartum bleeding in women with complete placenta previa
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Published on: June 6, 2020
1Department of Obstetrics and Gynecology, University Hospital of Bologna, Bologna, Italy. tullio.ghi@aosp.bo.it
Objective:
To evaluate if cervical length predicts prepartum bleeding and emergency Cesarean section in cases of placenta previa.
Methods:
Between September 2005 and September 2007, cervical length was measured by transvaginal ultrasound in women with complete placenta previa persisting into the third trimester of pregnancy. A complete follow-up of pregnancy was obtained in all cases.
Results:
Overall, 59 women were included in the study group. The mean +/- SD gestational age at ultrasound was 30.7 +/- 2.7 weeks and the cervical length was 36.9 +/- 8.8 mm. Cesarean delivery was performed in all cases, at a mean gestational age of 34.7 +/- 2.3 weeks. Twenty-nine (49.1%) of the women presented prepartum bleeding and 12 (20.3%) required an emergency Cesarean section prior to 34 completed weeks due to massive hemorrhage. Cervical length did not differ significantly between cases with and those without prepartum bleeding (35.3 +/- 9.3 mm vs. 38.4 +/- 8.2 mm; P = 0.18), but was significantly shorter among patients who underwent emergency Cesarean section < 34 weeks due to massive hemorrhage compared with patients who underwent elective Cesarean section (29.4 +/- 5.7 mm vs. 38.8 +/- 8.5 mm; P = 0.0006).
Conclusions:
Transvaginal sonographic cervical length predicts the risk of emergency Cesarean section < 34 weeks in women with complete placenta previa.

