OBJECTIVE: To explore the relationship between umbilical artery pulsatility index (UA PI), middle cerebral artery pulsatility index (MCA PI), cerebroplacental doppler ratio (CPR) and fetal weight at birth. Design: Retrospective analysis Setting: Hospital Patients: A total of 92 pregnant women at the 38th-42nd gestational weeks, whose UA PI, MCA PI, CPR were assessed and newborns’ birth weight measurements were available. Interventions: None Main outcome measures: The UA-PI, MCA PI and CPR values were expressed as multiple of the median (MoM) for gestation. Then, receiver–operating characteristics (ROC) curves were used to assess prediction of fetal weight equal or greater than 4000 g using MoM values of UA PI, MCA PI and CPR. RESULTS: There were 25 (27.2%) fetuses with weight equal or greater than 4000 g at birth. There was no correlation between doppler indices and birth weight. Area under curves on ROC curves, obtained by plotting sensitivity against false positive rate for detection of birth weight equal or greater than 4000 g, were not statistically significant for any of doppler indices CONCLUSION: There was no clinically relevant correlation between fetal weight and doppler indices.
Keywords: Doppler, fetal weight, impedance indices, umbilical artery, middle cerebral artery