We aimed to determine whether Doppler measurements obtained from the uterine and umbilical arteries in early pregnancy correlate with the subsequent development of pre-eclampsia, or the delivery of a small-for-gestational-age (SGA) baby. A follow-up study was carried out in 652 women with singleton pregnancies who had transvaginal uterine and umbilical artery Doppler examinations performed at 12–l6 weeks' gestation. Measurements included: the presence or absence of an early diastolic notch, vessel diameter, resistance index (RI), pulsatility index (PI), time-averaged mean velocity (TAV), maximum systolic velocity and volume flow in the right and left uterine arteries and RI and PI in the umbilical arteries. The main outcome measures were: intrauterine death, birth weight, pre-eclampsia (proteinuric pregnancy-induced hypertension, PPIH) and antepartum hemorrhage.
Twelve pregnancies terminated in the second trimester, and in 14 the outcome is unknown. In the remaining 626 women, 44 (7.0%) pregnancies ended in a premature delivery, 30 (4.7%) women developed PPIH, 60 (9.6%) infants were SGA (< 10th centile), of which 19 were < 5th centile and five were < 3rd centile, and 23 (3.7%) women suffered an antepartum hemorrhage. At 12–16 weeks, 205 (32.7%) women had bilateral (right and left) notching of the uterine artery waveforms. When compared to values from women with a normal pregnancy outcome, women who subsequently developed PPIH demonstrated a significant difference in mean uterine artery TAV (24.6 cm/s for PPIH vs. 33.25 cm/s for normal outcome, p < 0.003),volume flow (120.5 ml/min vs. 184.5 ml/min, p < 0.001) and elevated resistance (mean RI = 0.80 vs. 0.695, p < 0.001). In women with bilateral notching, there were significant differences between values for pregnancies with PPIH (odds ratio (OR) 42.02, 9.5% confidence interval(CI) 5.66, 311.99), being SGA at birth (OR: 8.61, 95% CI 4.0, 20.0) or delivering prematurely (OR 2.38, 95% CI 1.19,4.75), compared with pregnancies with a normal outcome.
We conclude that abnormal Doppler values, indicative of a failure to modify the uterine circulation in early pregnancy, are associated with premature delivery, the development of PPIH and the delivery of an SGA baby. This information may be of value in increasing our understanding of the pathophysiological events that lead to the subsequent development of uteroplacental complications such as pre-eclampsia. Copyright © 1997 International Society of Ultrasound in Obstetrics and Gynecology