(1126) Cervical funneling is more predictive of preterm birth than cervical length alone in nulliparous women

Friday, February 10, 2023

3:30 PM – 5:00 PM

Objective: Universal mid-trimester cervical length (CL) screening is a well-accepted practice for detection of women at risk of spontaneous preterm birth (sPTB). In those identified with a short cervix, progesterone supplementation is recommended. However, current guidelines do not consider a short cervix an indication for cerclage without a history of sPTB as it has poor sensitivity for this outcome. It is currently unclear if other sonographic features such as cervical funneling can identify a higher sPTB risk in a population without prior sPTB.

Study Design: This was a secondary analysis of the nuMom2b study, which enrolled a large prospective observational cohort of pregnant nulliparous women. Patients were stratified based on CL < 25mm or ≥25mm and presence or absence of funneling at the time of cervical length evaluation between 16-22 weeks’ gestation. Logistic regression was used to calculate adjusted odds ratios (aOR) and 95% confidence intervals (CI) for sPTB adjusting for confounders. A Kaplan-Meier survival analysis was performed between groups and gestational age at delivery.

Results: 7,648 nulliparous women were included in the analysis. There were 169 (2.2%) women identified with a short CL < 25 mm and 52 (0.7%) with funneling. While a short CL had a higher risk of PTB (Table 1), a short CL was detected in only 24 (7.1%) of women who ultimately had a sPTB. The presence of a funnel was independently associated with higher odds of sPTB (OR 3.4, CI 1.9-8.1) when compared to CL < 25mm (OR 2.7, CI 1.7-4.4). On survival analysis, a short CL with funneling showed the lowest mean gestational age at delivery (Figure 2, p< .001).

Conclusion: In a nulliparous population without prior sPTB, transvaginal cervical length alone is a poor predictor of preterm delivery, but presence of funneling significantly increases risk. This may identify a population of women who would benefit from cerclage.

Primary & Presenting Author(s)

Ralitza H. Peneva, MD
Medical University of South Carolina
Johns Island, South Carolina, United States

Coauthor(s)

Brittany Austin, MD
Resident
Medical University of South Carolina
Charleston, South Carolina, United States
Benjamin M. Muller, MD
Maternal Fetal Medicine Fellow
The Medical University of South Carolina
Charleston, South Carolina, United States
MA
Mallory Alkis, MD
MUSC
Charleston, South Carolina, United States
MF
Matthew M. Finneran, MD
Assistant Professor
Medical University of South Carolina
Charleston, South Carolina, United States