OBJECTIVES: To investigate the relationship between total uterine artery blood volume flow rate (TVFR) and birthweight and gestation at delivery and to establish normal ranges of TVFR through pregnancy. METHODS: A prospective cohort study at University College London Hospital, in which 334 nulliparous women booking for antenatal care had measurement of TVFR by transabdominal ultrasound at 12, 20 and 24 weeks. RESULTS: 551 scans were performed. There was a significant and positive correlation between total uterine blood volume flow at 11-13 weeks (TVFR1) and 22-26 weeks (TVFR2) and birthweight. For every 100 unit increase in TVFR1 and TVFR2, there was a 45 g and 27 g increase in birthweight respectively. There was also a positive association between TVFR1 and gestation at delivery, with a 1.4 day increase in gestation for every 100 unit increase of TVFR1. CONCLUSION: Ultrasound measurement of TVFR in the first trimester is significantly associated with both birth weight and gestation at delivery
