Outcome after second-trimester amniocentesis and first-trimester chorionic villus sampling for prenatal diagnosis in multiple gestations.

PURPOSE

The purpose of this study was to classify pregnancy loss and fetal loss as well as the influence of maternal risk factors in multiple pregnancies.

METHODS AND MATERIALS

Details of the procedure and pregnancy outcome of all patients were extracted from the clinical audit database of two tertiary centers. The files were collected in the time from January 1993 to May 2011.  The procedure-related pregnancy and fetal loss rate was classified as all unplanned abortions without important fetal abnormalities or obstetric complications within 14 days after AC and CVS.

RESULTS

We had a total number of 288 multiple pregnancies with a total of 637 fetuses. After the exclusion of 112 pregnancies with abnormal karyotype or fetal abnormalities detected by ultrasound as well as cases of selective feticide, repeated invasive procedures and monochorionic-monoamniotic pregnancies, 176 pregnancies and 380 fetuses were left for final analysis. Overall 132 amniocenteses and 44 chorionic villous sampling procedures were performed. The total pregnancy loss rate was 8.0 % (14/176), 6.1 % (n = 8) for amniocentesis and 13.6 % (n = 6) for CVS.  The procedure-related pregnancy loss rate was 3.4 %, 2.3 % after amniocentesis (3 cases) and 6.8 % after CVS (3 cases). There was no statistical significance between the two procedures (p = 0.15).

CONCLUSION

The procedure-related loss rate of 3.4 % can be compared to the rates in the literature. The higher loss rates in multiple pregnancies than in singleton pregnancies have to be discussed when counseling parents.