Premium
Ultrasound screening for fetal growth restriction at 36 vs 32 weeks' gestation: a randomized trial ( ROUTE )
Author(s) -
Roma E.,
Arnau A.,
Berdala R.,
Bergos C.,
Montesinos J.,
Figueras F.
Publication year - 2015
Publication title -
ultrasound in obstetrics and gynecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.202
H-Index - 141
eISSN - 1469-0705
pISSN - 0960-7692
DOI - 10.1002/uog.14915
Subject(s) - medicine , gestation , obstetrics , pregnancy , odds ratio , fetus , birth weight , randomized controlled trial , fetal distress , gestational age , genetics , biology
Objective To compare the utility of routine third‐trimester ultrasound examination at 36 weeks' gestation with that at 32 weeks in detecting fetal growth restriction ( FGR ). Methods This was an open‐label parallel randomized trial ( ROUTE study) conducted at a single general hospital serving a geographically well‐defined catchment area in Barcelona, Spain, between May 2011 and April 2014. Women with no adverse medical or obstetric history and a singleton pregnancy without fetal abnormalities at routine second‐trimester scan were assigned randomly to undergo a scan at 32 weeks' gestation ( n = 1272) or at 36 weeks' gestation ( n = 1314). Primary outcome measures were detection rates of FGR (customized birth weight < 10 th centile) and severe FGR (customized birth weight < 3 rd centile). Results There were no significant differences in perinatal outcome between those who underwent a scan at 32 weeks' gestation and those who underwent a scan at 36 weeks' gestation. Severe FGR at birth was associated significantly with emergency Cesarean delivery for fetal distress (odds ratio ( OR ), 3.4 (95% CI , 1.8–6.7)), neonatal admission ( OR , 2.23 (95% CI , 1.23–4.05)), hypoglycemia ( OR , 9.5 (95% CI , 1.8–49.8)) and hyperbilirubinemia ( OR , 9.0 (95% CI , 4.6–17.6)). Despite similar false‐positive rates ( FPRs ) (6.4% vs 8.2%), FGR detection rates were superior at 36 vs 32 weeks' gestation (sensitivity, 38.8% vs 22.5%; P = 0.006), with positive and negative likelihood ratios of 6.1 vs 2.7 and 0.65 vs 0.84, respectively. In cases of severe FGR , FPRs for both scans were also similar (8.5% vs 8.7%), but detection rates were superior at 36 vs 32 weeks' gestation (61.4% vs 32.5%; P = 0.008). Positive and negative likelihood ratios were 7.2 vs 3.7 and 0.4 vs 0.74, respectively. Conclusion In low‐risk pregnancies, routine ultrasound examination at 36 weeks' gestation was more effective than that at 32 weeks' gestation in detecting FGR and related adverse perinatal and neonatal outcomes. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.