The objective was to evaluate the best predictors of adverse perinatal outcome (APO) in foetuses examined up to 34 weeks and delivered by spontaneous or induced labour. This was a retrospective study of 129 pregnancies that underwent an ultrasound Doppler examination at 23-34 weeks and entered into labour within 30 days. Cerebroplacental ratio (CPR) and mean uterine artery pulsatility index (mUtA PI) were converted into multiples of the median (MoM) and estimated foetal weight (EFW) into centiles to adjust for gestational age (GA). Sonographic and clinical parameters were evaluated using logistic regression analysis.The multivariable model for the prediction of APO presented a notable accuracy: Detection rate (DR) was 39.5% for a false positive rate (FPR) of 5% and 56.8% for a FPR of 10%, AUC 0.82, p < .0001. Significant predictors were GA, EFW centile, and CPR MoM, but not mUtA PI MoM. Moreover, the type of labour onset did not exert any influence on APO. In conclusion, up to 34 weeks, prediction of APO after spontaneous or induced labour may be done measuring CPR and EFW.IMPACT STATEMENTWhat is already known on this subject? Earlier in pregnancy, foetal growth restriction is caused by placental disease causing progressive hemodynamic changes. These changes have been exhaustively described. Conversely, information about the best predictors of adverse outcome is scarce.What do the results of this study add? The findings of this study show that prior to 34 weeks and up to 1 month before labour, labour outcome might be predicted by gestational age, foetal cerebroplacental ratio (CPR) and estimated foetal weight (EFW).What are the implications of these findings for clinical practice and/or further research? If CPR behaves as a good marker of outcome not only at the end of pregnancy but also earlier in gestation, it might be interrogated along with EFW in foetuses attempting vaginal delivery to determine the risk of adverse outcome.
Keywords: Cerebroplacental ratio; adverse perinatal outcome; middle cerebral artery Doppler; umbilical artery Doppler; uterine artery Doppler.