Association of Second-Trimester Cervical Length With Prolonged Pregnancy

Area of Science:

• Maternal-Fetal Medicine
• Obstetrics
• Pregnancy Outcomes

Background:

• Cervical length measurement in the second trimester is a routine obstetric procedure.
• Predicting prolonged pregnancy (post-term delivery) is crucial for optimizing obstetric management.

Purpose of the Study:

• To investigate the association between second-trimester cervical length and the risk of prolonged pregnancy.
• To determine if cervical length can serve as a predictor for pregnancies extending beyond 41 weeks of gestation.

Main Methods:

• A cohort study involving 9,165 nulliparous women with singleton pregnancies.
• Cervical length was measured between 18 and 24 weeks of gestation and categorized into quartiles.
• Statistical analyses (bivariable and multivariable) were used to assess the association with prolonged pregnancy.

Main Results:

• A significant association was observed between increasing quartiles of cervical length and a higher likelihood of prolonged pregnancy (12.9% to 18.6%).
• This association remained statistically significant after adjusting for potential confounding factors.
• Secondary analysis restricted to women reaching at least 39 weeks confirmed the primary findings.

Conclusions:

• Second-trimester cervical length is a significant predictor of prolonged pregnancy in nulliparous women.
• Longer cervical length in the second trimester is associated with an increased risk of delivering at or beyond 41 weeks of gestation.