[Prognostic value of fetal aortic isthmus Doppler waveform in intrauterine growth retardation: prospective longitudinal study].

OBJECTIVE: Our purpose was to determine whether the use of aortic isthmus Doppler waveform analysis in growth restricted fetuses delivered at 28 to 38 weeks predicts perinatal outcomes. MATERIAL AND METHODS: Prospective longitudinal study including singleton non-malformed euploid fetuses with accurate dating and diagnosed as growth restricted (abdominal circumference<10th percentile) and who were followed up at our institution and delivered<10 days after the last Doppler. Timing of delivery was collegial. Perinatal mortality and morbidity outcomes were compared in cases with anterograde blood flow versus retrograde net blood flow in aortic isthmus. Relative risk (RR) were calculated with 95% CI and P<0,05 was considered significant. RESULTS: Thirty-two cases were considered for analysis: growth-restricted foetuses with anterograde blood flow (n=26) versus retrograde net blood (n=6). Maternal demographic characteristics in the two groups were similar and exceptions made of femur length average values for fetal biometrics were not significantly different. Doppler velocimetry results at the uterine, umbilical and cerebral arteries were similar in the two groups. Gestational age at delivery and birth weight were similar in both groups (respectively (239.65 20.1 vs. 247.3 16.4 (days) (p=0.349) and 1748.8 gr 468.7 vs. 1933.3 gr 468.7 (p=0.408)). There was a statistically significant increase in perinatal mortality in retrograde net blood flow group: 8.66 [IC 95% 2.03 - 36.84]. An interesting finding was that neonates with aortic isthmus retrograde net blood flow were more frequently born by cesarean delivery because of a suspected fetal compromise RR=3.22 CI 95% [1.29-8]. CONCLUSION: In our study Doppler identification of aortic isthmus retrograde net blood flow in growth-restricted fetuses was associated with an increase of perinatal death.