Purpose To assess the longitudinal variation of the ratio of umbilical and cerebral artery pulsatility index (UCR) in late preterm fetal growth restriction (FGR). Materials and Methods A prospective European multicenter observational study included women with a singleton pregnancy, 32 +0-36 +6, at risk of FGR (estimated fetal weight [EFW] or abdominal circumference [AC] <10 th percentile, abnormal arterial Doppler or fall in AC from 20-week scan of >40 percentile points). The primary outcome was a composite of abnormal condition at birth or major neonatal morbidity. UCR was categorized as normal (<0.9) or abnormal (≥0.9). UCR was assessed by gestational age at measurement interval to delivery, and by individual linear regression coefficient in women with two or more measurements. Results 856 women had 2770 measurements; 696 (81%) had more than one measurement (median 3 (IQR 2-4). At inclusion, 63 (7%) a UCR ≥0.9. These delivered earlier and had a lower birth weight and higher incidence of adverse outcome (30% vs. 9%, relative risk 3.2; 95%CI 2.1-5.0) than women with a normal UCR at inclusion. Repeated measurements after an abnormal UCR at inclusion were abnormal again in 67% (95%CI 55-80), but after a normal UCR the chance of finding an abnormal UCR was 6% (95%CI 5-7%). The risk of composite adverse outcome was similar using the first or subsequent UCR values. Conclusion An abnormal UCR is likely to be abnormal again at a later measurement, while after a normal UCR the chance of an abnormal UCR is 5-7% when repeated weekly. Repeated measurements do not predict outcome better than the first measurement, most likely due to the most compromised fetuses being delivered after an abnormal UCR.
|Journal||Ultraschall in der Medizin (Stuttgart, Germany : 1980)|
|Early online date||2021|
|Publication status||E-pub ahead of print - 2021|