Prediction of perinatal outcome in fetuses suspected to have intrauterine growth restriction: Doppler US study of fetal cerebral, renal, and umbilical arteries

PURPOSE: To determine and compare the diagnostic performance of fetal middl e cerebral (MCA), renal (RA), and umbilical (UA) arterial Doppler ultrasono graphy (US) for prediction of adverse perinatal outcome in suspected intrau terine growth restriction (IUGR). MATERIALS AND METHODS: Two hundred ninety-three small-for-gestational age f etuses (24-39 weeks at recruitment and US-estimated weight or abdominal cir cumference below 10th percentile) were prospectively examined with Doppler US of the UA, MCA, and RA. Clinicians were blinded to MCA and RA Doppler me asurements. RESULTS: Seventy-six fetuses (25.9%) had at least one major or minor advers e perinatal outcome. Major outcomes included stillbirth, neonatal death, ne urologic complication, and necrotizing enterocolitis. The MCA pulsatility i ndex (PI), compared with the UA PI and RA PI, was more sensitive (72.4% vs 44.7% and 8.3%) but less specific (58.1% vs 86.6% and 92.6%) In predicting adverse outcome. The UA PI had the highest positive likelihood ratio(ratio, 3.3); the MCA PI had the lowest negative likelihood ratio (ratio, 0.48). W hen gestational age at the first Doppler US examination was less than 32 we eks, the MCA PI had a sensitivity of 95.5% and negative predictive value of 97.7% for major adverse outcome (negative likelihood ratio, 0.10). CONCLUSION: In suspected IUGR, while an abnormal UA PI is a better predicto r of adverse perinatal outcome than an abnormal MCA or RA PI, a normal MCA PI may help to identify fetuses without major adverse perinatal outcome, es pecially before 32 weeks gestational age.