Am J Perinatol 2017; 34(09): 922-926
DOI: 10.1055/s-0037-1601310
Original Article
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Is the Relationship between Short Interpregnancy Interval and Preterm Birth Related to a Short Cervix?

S. Govindappagari
1  Department of Obstetrics and Gynecology, New York Presbyterian Hospital/Queens, Weill Cornell College of Medicine, New York, New York
,
N. Zork
2  Department of Obstetrics and Gynecology, Columbia University Medical Center, New York, New York
,
A. Merriam
2  Department of Obstetrics and Gynecology, Columbia University Medical Center, New York, New York
,
C. Gyamfi-Bannerman
2  Department of Obstetrics and Gynecology, Columbia University Medical Center, New York, New York
› Author Affiliations
Further Information

Publication History

22 January 2017

15 February 2017

Publication Date:
20 March 2017 (eFirst)

Abstract

Objective Our objective was to determine if the relationship between interpregnancy interval (IPI) and preterm delivery was related to cervical shortening.

Methods This is a secondary analysis of a prospective cohort study designed to assess the relationship between cervical length (CL) and preterm delivery. Multiparous patients, who had transvaginal CLs obtained at 22 to 24 weeks and complete pregnancy outcome data available were included. The women were divided into two groups: Group 1 with an IPI of ≤ 1 year and Group 2 with an IPI of > 1 year. The primary outcome was short cervix (CL < 2.5 cm) at 24 weeks. The secondary outcome was the incidence of preterm delivery < 37 weeks. Interaction between short cervix and IPI was examined in a regression model.

Results There were 155 women in Group 1 and 328 women in Group 2. There was no difference in the incidence of short cervix between groups (10.0% in Group 1 and 12.9% in Group 2, p = 0.35). In a logistic regression model, short IPI and short cervix were independently associated with preterm birth.

Conclusion The relationship between short IPI and preterm birth is not explained by a short cervix. They remain independent risk factors for preterm birth.

Note

This study was presented at the 63rd Annual Meeting of the Society for Reproductive Investigation in Montreal, Canada, Abstract #949.