Am J Perinatol 2020; 37(01): 014-018
DOI: 10.1055/s-0039-1694006
SMFM 2019
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Serial Cervical Length Evaluation in Low-Risk Women with Shortened Cervical Lengths in the Midtrimester: How Many Will Dilate Prior to 24 Weeks?

Kelly B. Zafman
1  Department of Obstetrics, Gynecology, and Reproductive Science, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania
,
Andrei Rebarber
2  Department of Obstetrics, Gynecology, and Reproductive Science, Icahn School of Medicine at Mount Sinai, New York, New York
3  Maternal Fetal Medicine Associates, PLLC, New York, New York
,
Nathan S. Fox
2  Department of Obstetrics, Gynecology, and Reproductive Science, Icahn School of Medicine at Mount Sinai, New York, New York
3  Maternal Fetal Medicine Associates, PLLC, New York, New York
› Author Affiliations
Further Information

Publication History

28 May 2019

25 June 2019

Publication Date:
09 August 2019 (online)

Abstract

Objective To determine what proportion of women with a short cervical length (CL) without a history of spontaneous preterm birth (SPTB) will ultimately be dilated at <24 weeks.

Study Design This is a retrospective cohort study of women with singleton pregnancies with a short CL (≤25 mm) between 16 and 22 weeks' gestational age (GA). We excluded women with a history of SPTB. We examined the progression of women with short CL based on the CL measurement and GA at diagnosis. The primary outcome was cervical dilation or spontaneous delivery <24 weeks.

Results A total of 163 women were included, of whom 27 (16.6%) were ultimately dilated and 4 (2.5%) had pregnancy loss by 24 weeks. The median GA at diagnosis of short CL was 195/7 (range: 15–22) weeks. Women with a CL <15 mm were more likely to have cervical dilation or loss prior to 24 weeks than women whose CL was 15 to 25 mm (42.5 vs. 11.9%, <0.001, adjusted odds ratio: 3.72, 95% confidence interval: 1.52–9.09). GA at diagnosis was not associated with risk of progression.

Conclusion In women with a short CL without a history of SPTB, the risk of dilation or pregnancy loss <24 weeks is significant, approaching 50% for women with a CL <15 mm.

Note

This study was presented as a poster at the Annual Scientific Meeting of the Society for Maternal-Fetal Medicine, February 15–17, 2019, Las Vegas, NV.