Comprehensive assessment of fetal wellbeing in intrauterine growth restriction: biophysical profile and doppler cerebroplacental ratio

ABSTRACT

The current routine prenatal surveillance tests such as the non-stress test and fetal biophysical profile [BPP] may not be sensitive or specific enough to detect fetuses with an early compromise. Studies suggest that the cerebroplacental ratio [CPR] may be a highly sensitive Doppler index for assessment of wellbeing and prediction of outcome in fetuses with intrauterine growth restriction [IUGR]. To evaluate [1] the screening efficiency of Doppler CPR, compared with BPP, for the prediction of IUGR and the associated perinatal complications; and [2] whether the additional use of CPR improves the prediction of such outcomes over BPP alone. A comparative cross-sectional study. Department of Obstetrics and Gynecology, Kasr El-Aini Hospital, Cairo University. Fifty singleton pregnancies at risk for IUGR. Cases were managed with weekly or twice weekly BPP, and Doppler velocimetry of the umbilical artery [UA] and middle cerebral artery [MCA] was performed when delivery is indicated. The CPR, defined as the MCA-RI divided by the UA-RI, was considered abnormal if <1.0. Adverse perinatal outcome was defined as any combination of IUGR and perinatal complications. The perinatal outcomes were correlated to the results of BPP and CPR, and the accuracy of BPP and CPR in the prediction of adverse outcome was calculated. Sixteen cases [32%] had normal outcome and 34 cases [68%] had adverse outcome. The BPP and CPR were significantly lower in cases with adverse outcome [p=0.002 and 0.001, respectively]. Cases with abnormal BPP and CPR had a very high risk of adverse outcome [27/28; 96%]. The CPR was comparable to BPP; and the correlation of BPP and CPR increased the accuracy of prediction of adverse outcome as shown by sensitivity, specificity, +ve predictive value, -ve predictive value, overall accuracy, likelihood ratio +ve, and likelihood ratio-ve of 79%, 75%, 87%, 63%, 78%, 3.16, and 0.28, respectively, for BPP alone; and 82%, 69%, 85%, 65%, 78%, 2.65, and 0.26, respectively, for CPR alone; compared to 79%, 94%, 96%, 68%, 84%, 13.17, and 0.22, respectively, for both BPP and CPR. The main finding was an increase in the perinatal risk when abnormal BPP and CPR are observed. The additional use of CPR appears to improve risk prediction over BPP alone