THE ROLE OF DOPPLER VELOCIMETRY IN THE STRUCTURALLY NORMAL 2ND-TRIMESTER FETUS WITH ELEVATED LEVELS OF MATERNAL SERUM ALPHA-FETOPROTEIN

Umbilical and uterine artery velocimetry was performed in 199 second-t rimester pregnancies undergoing sonographic examination for unexplaine d elevated levels of maternal serum alpha-fetoprotein in order to eval uate the efficacy of Doppler waveforms for the prediction of adverse p erinatal outcome. A total of 169 pregnancies resulted in term deliveri es of infants with appropriate growth for age, and 30 pregnancies (15% ) had adverse outcomes, including preterm delivery, growth retardation and death. The umbilical artery systolic/diastolic ratio was not stat istically different in the two groups (3.9 vs. 4.2, p = 0.16). The ute rine artery systolic/diastolic ratio was slightly greater in the group with abnormal outcome (5.7) than in the group with normal outcome (3. 3), but the difference was not significant (p = 0.11). Forty-six patie nts had uterine artery waveforms that exhibited an early diastolic not ch. Of these, 31 had a grade I notch in which the lowest part of the n otch was not greater than one half of the diastolic frequency shift. F ifteen patients had a severe or grade II notch in which the deepest pa rt of the diastolic notch was less than half of the diastolic flow. In patients with either no diastolic or grade I uterine artery notch, th e incidence of adverse outcomes was 231184 (12.5%). In patients with a grade II notch, 7/15 (47%) had a poor outcome. The rate of adverse ou tcome in patients with a grade II notch was more than three times that observed in women without severe uterine notch, yielding a relative r isk of 3.4 (95% CI 1.9-6.0). Thus, the presence of a grade II uterine artery notch on second-trimester sonographic evaluation is associated with an increased risk for adverse perinatal outcome over unexplained elevated levels of maternal serum alpha-fetoprotein.