Natural history of cervical funneling in women at high risk for spontaneous preterm birth.
Publication/Presentation Date
4-1-2007
Abstract
OBJECTIVE: To estimate the natural history of funneling in the second trimester by transvaginal ultrasonograms and whether funneling increases the risk of spontaneous birth.
METHODS: Secondary analysis of a blinded, multi-center observational study of women with at least one prior spontaneous preterm birth at 16.0-31.9 weeks who subsequently carried singleton gestations. Cervical length, funneling (membrane prolapse greater than or equal to 5 mm), funnel shape, and dynamic changes were recorded at 16-18 weeks, and then every 2 weeks until 23.9 weeks. Managing obstetricians were blinded to the ultrasonography results. The primary outcome was gestational age at delivery.
RESULTS: Five hundred ninety scans were performed in 183 women, of which 60 (33%) had funneling observed on at least one of the serial evaluations. These 60 women delivered at an earlier gestational age at delivery than the 123 women without funneling (31.7+/-7.9 weeks compared with 36.9+/-4.4 weeks; P< .001). In the 60 women with funneling on at least one evaluation, the progression over time of internal os cervical anatomy from a "T" to a "V" to a "U" shape was associated with earlier gestational age at delivery, whereas resolution of "V" shape funnels was associated with term delivery. Women with a shortened cervical length less than 25 mm (n=60) had a similar gestational age at birth with or without funneling (30.6+/-8.0 weeks compared with 31.9+/-6.6 weeks; P=.59). After controlling for the shortest observed cervical length, largest funnel percent was not a significant independent risk factor.
CONCLUSION: The natural history of second-trimester funneling has significant variability and a significant association with earlier gestational age at delivery. As an independent finding, funneling does not add appreciably to the risk of early gestational age at delivery associated with a shortened cervical length.
LEVEL OF EVIDENCE: II.
Volume
109
Issue
4
First Page
863
Last Page
869
ISSN
0029-7844
Published In/Presented At
Berghella, V., Owen, J., MacPherson, C., Yost, N., Swain, M., Dildy, G. A., 3rd, Miodovnik, M., Langer, O., Sibai, B., & National Institute of Child Health and Human Development (NICHD) Maternal-Fetal Medicine Units Network (MFMU) (2007). Natural history of cervical funneling in women at high risk for spontaneous preterm birth. Obstetrics and gynecology, 109(4), 863–869. https://doi.org/10.1097/01.AOG.0000258276.64005.ce
Disciplines
Business Administration, Management, and Operations | Health and Medical Administration | Management Sciences and Quantitative Methods
PubMedID
17400847
Department(s)
Administration and Leadership
Document Type
Article