Prenatal detection of fetal anomalies by ultrasonography in the second trimester: Our first results from Turkey

Objective The aim of this study was to determine our anomaly prevalence in a low-risk population, to observe the distribution of anomalies detected by ultrasound and to evaluate the accuracy of the antenatal detection of malf ormations by second-level ultrasound examination during weeks 16-24 of gest ation. Materials and methods Antenatal follow-up of 8420 pregnant women was perfor med at the antenatal unit of the Zeynep Kamil maternity hospital from May 1 996 to July 1998. All women underwent a screening ultrasonographic examinat ion of fetal anatomy at 16-24 weeks of gestation. The distribution of detec ted anomalies according to organ systems, the incidence of anomalous infant s, the prevalence of fetal anomalies and the sensitivity and specificity we re evaluated. Results During the study period of 27 months, 160 anomalies were recorded i n 110 fetuses. It was found that the anomaly prevalence was 1.58%; the posi tive and negative predictive values were 89.6% and 99.8%, respectively. Our detection rates of fetal anomalies were 92.3% for the central nervous syst em, 80% for the musculoskeletal system, 61.5% for the genitourinary system, 50% for craniofacial anomalies and 23.5% for the cardiovascular system. Conclusion Second-level ultrasound scanning at 16-24 weeks of gestation sho uld be an essential procedure for diagnosing prenatal malformations. It rev eals important data when performed in tertiary centers by educated and expe rienced sonographers with a uniform program.