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.
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.
Authors: Melissa S Mancuso; Jeff M Szychowski; John Owen; Gary Hankins; Jay D Iams; Jeanne S Sheffield; Annette Perez-Delboy; Vincenzo Berghella; Debora A Wing; Edwin R Guzman Journal: Am J Obstet Gynecol Date: 2010-09 Impact factor: 8.661
Authors: G R Saade; E A Thom; W A Grobman; J D Iams; B M Mercer; U M Reddy; A T N Tita; D J Rouse; Y Sorokin; R J Wapner; K J Leveno; S C Blackwell; M S Esplin; J E Tolosa; J M Thorp; S N Caritis; J P Vandorsten Journal: Ultrasound Obstet Gynecol Date: 2018-10-26 Impact factor: 7.299
Authors: A Ostadi Moghaddam; Z Lin; M Sivaguru; H Phillips; B L McFarlin; K C Toussaint; A J Wagoner Johnson Journal: Acta Biomater Date: 2021-12-25 Impact factor: 8.947