Ultrasound estimated fetal weight slightly below the median is associated with increased risk of spontaneous preterm birth.

Background This study investigates the possible relationship between ultrasound estimated fetal weight (EFW) at third trimester and the risk of preterm birth following spontaneous preterm labor in otherwise uncomplicated pregnancies. Methods We performed a nested casecontrol study including 281 cases of spontaneous preterm labor with preterm delivery in the third trimester and 3372 matched controls within a cohort of 6207 consecutive pregnant women. Pregnancies with fetal growth restriction (birth weight <10th centile of population-based normograms) or fetal anomalies were not included. EFW was calculated by using Hadlock's formula and converted to fetal gender adjusted multiples of median (MoM) for each gestational age. Results EFW correlated with birth weight (r?=?0.959, p?更多