Indications for Fetal Invasive Procedures at the End of an Era

Purpose The introduction of first trimester screening has changed the attitude towards and the number of invasive procedures in prenatal medicine. We evaluated the indications in patients who underwent an invasive procedure before the introduction of the analysis of cell-free fetal DNA in maternal plasma in prenatal medicine. Materials and Methods 680 pregnant women between the 10th and 35th week of gestation were included in the study from July 1, 2010 to June 30, 2013. Retrospectively, we reviewed the data for indications, type, gestational age at the time of, and result of the invasive procedure. Results We performed 247 chorionic villus samplings (CVSs) and 433 amniocenteses (ACs) during the study interval. The main indication for CVS was an abnormal result from the first trimester screening (75 %), whereas in AC it was advanced maternal age (39 %). 33 % of all CVSs and 8 % of all ACs revealed an abnormal karyotype. All these findings were significantly different. Conclusion Despite the broad acceptance of first trimester screening, there are still women undergoing AC for advanced maternal age, whereas abnormal results from the first trimester screening are the most common indication for CVS. Based on our results, we can conclude that indications derived from first trimester findings have the highest positive predictive value.