A report on 158 cases of transcervical chorionic villus sampling.

Between 1989 and 1994 first trimester transcervical chorionic villus sampling was offered to 158 patients after proper counselling. The gestational age range was 9-12 weeks. The most important indication was advanced maternal age (75.4%). Adequate sampling after two, and a maximum of three attempts, was achieved in 98% and 99.3% of patients respectively. After the first year of the study karyotyping using the direct method alone was successful in 96% of cases. The success of karyotyping cultures was 98%. Excluding one false positive result the rate of fetal karyotypic abnormalities was 4.8%. 5 spontaneous abortions occurred (3.2%), all in patients of advanced maternal age. Moderate or severe vaginal bleeding occurred in 6.7% of the patients. There was no case of chorioamnionitis.