Doppler and maternal serum screening in the prediction of pregnancy complications* Doppler e marcadores séricos maternos na predição de complicações da gestação

OBJECTIVE: To compare the effectiveness of uterine artery Doppler and maternal serum screening in the prediction of pregnancy complications. MATERIALS AND METHODS: Prospective study with 49 primigravidae at their 18th gestational week, when a blood sample was collected for serum dosage by chemiluminescence (alpha-fetoprotein, human chorionic gonadotropin and nitric oxide) and radioimmunoassay (atrial natriuretic peptide). Uterine artery Doppler was performed between the 24th and 26th gestational weeks, for determining the presence or absence of notch in the flow velocity waveform. The non-parametric Mann-Whitney test was utilized for statistical analysis, and the Fisher exact test for analysis of qualitative parameters. RESULTS: Sensitivity, specificity, positive and negative predictive values were, respectively, 8.3%, 97.0%, 50.0% and 74.4% for alpha-fetoprotein; 8.3%, 87.9%, 20.0% and 72.5% for human chorionic gonadotropin; 16.7%, 97.0%, 33.3% and 76.2% for atrial natriuretic peptide; and 16.7%, 93.9%, 50.0% and 75.6% for nitric oxide. The uterine artery Doppler sensitivity was 75.0%, specificity 63.6%, positive predictive value 57.1%, and negative predictive value 87.5%. CONCLUSION: Uterine artery Doppler is an effective method for prediction of pregnancy complications as compared with maternal serum screening in low risk populations.