Multicenter screening for pre-eclampsia and fetal growth restriction by transvaginal uterine artery Doppler at 23 weeks of gestation

Objective To determine the value of transvaginal color Doppler assessment o f the uterine arteries at 23 weeks of gestation in predicting the subsequen t development of pre-eclampsia and fetal growth restriction. Patients and methods Women with singleton pregnancy. es attending for routi ne ultrasound examination at 23 weeks in anyone of seven hospitals underwen t Doppler assessment of the uterine arteries. The presence of an early dias tolic notch in the waveform was noted, and the mean pulsatility index of th e two arteries was calculated. Screening characteristics in the prediction of pre-eclampsia and the delivery of a low birth-weight infant were calcula ted. Results Doppler examination of the uterine arteries was attempted in 8335 c onsecutive singleton pregnancies, satisfactory waveforms were obtained from both vessels in 8202 (98.4%) cases and complete outcome data were availabl e in 7851 (95.7%) of these. The mean gestational age was 23 (range, 22-24) weeks. The mean uterine artery pulsatility index did not change significant ly with gestation (r = -0.0078; P = 0.483); the median value was 1.04 and t he 95th centile was 1.63. In 9.3% of cases early diastolic notches in the w aveform from both uterine arteries were present and in an additional 11.1% of cases there were notches unilaterally. Pre-eclampsia with fetal growth r estriction occurred in 42 (0.5%) cases, pre-eclampsia without fetal growth restriction in 71 (0.9%) and fetal growth restriction without pre-eclampsia in 698 (8.9%). The sensitivity of increased pulsatility index above the 9S th centile (1.63) for pre-eclampsia with fetal growth restriction was 69%, for Pre-eclampsia without fetal growth restriction was 24%, for fetal growt h restriction without pre-eclampsia was 13%, for pre-eclampsia irrespective of fetal growth restriction was 41% and for fetal growth restriction irres pective of pre-eclampsia was 16%. The sensitivity of fetal growth restricti on defined by the 5th rather than the 10th centile was higher (19% vs. 16%) . The sensitivity for both pre-eclampsia and fetal growth restriction was i nversely related to the gestational age at delivery; when delivery occurred before 32 weeks, the sensitivity for all cases of pre-eclampsia with fetal growth restriction, pre-eclampsia without fetal growth restriction and fet al growth restriction without pre-eclampsia increased to 93%, 80% and 56%, respectively. The sensitivity of bilateral notches in predicting pre-eclamp sia and/or fetal growth restriction was similar to that of increased pulsat ility index but the screen-positive rate with notches (9.3%) was much highe r than that with i. ncreased pulsatility index (5.1%). Conclusions A one-stage color Doppler screening program at 23 weeks identif ies most women who subsequently develop severe pre-eclampsia and/or fetal g rowth restriction.