Accuracy of prenatal sonography in terminated pregnancies - a retrospective analysis of results and parameters of influence

Objective: The aim of the study was to analyse the accuracy of prenatal son ography in terminated pregnancies and the influence of factors like personn el and standard of technique and organisation on the quality of prenatal so nography for the detection of fetal anomalies. Material and Methods: The retrospective study includes 64 cases with termin ation of pregnancy from 1989 to 1997. We analyse prenatal sonographic and p ostnatal pathological findings of fetus, placenta and umbilical cord. Furth ermore we compare two time periods (1989-93 and 1994-97) with different ult rasound conditions. Results: In 36 cases (56%) the prenatal diagnosis was exact. In 7 cases (11 %) autopsy could not confirm all findings (false positive), whereas autopsy detected additional anomalies in 18 cases (28%) (false negative). The diag nosis was not correct in 3 cases (5%), whereby 2 pregnancies were terminate d without proved somatic and chromosomal anomalies. Compared to 1989-93 the rate of false-positive (12 vs. 5) as well as false-negative (9 vs. 3) diag noses decreased significantly (p < 0.002) in cases with major anomalies (he art, central nervous system). Conclusion: We conclude that the improvement of the level of organisation, personnel and technical equipment has relevant impact on the accuracy of pr enatal sonography. Autopsy as a method of quality control is absolutely nec essary.