CHORION VILLUS SAMPLING - TRANSCERVICAL OR TRANSABDOMINAL

EDITORIAL COMMENT: This study provides interesting information on the relative effectiveness of chorion villus sampling performed transcervically and transabdominally regarding obtaining a suitable specimen. The results seem to indicate that the abdominal route is preferred unless contraindicated, because of a lesser risk of infection. Although the series is not a controlled trial with alternate patients receiving transcervical or the transabdominal technique, the results seem clinically meaningful. It is important to note that the spontaneous abortion rate following chorion villus sampling by any route is less than the rate observed in normal obstetric practice when early ultrasound has not been used to exclude cases of unsuspected missed abortion. This explains the remarkably low incidence of miscarriage following chorion villus sampling. It will be interesting to see whether the low complication rate of chorion villus sampling will eventually result in the test being offered to all patients rather than those that are high risk — it should be remembered that the majority of recognizably malformed fetuses are born to patients without any risk factor. This is already the practice in some areas of the United States of America. The present state of the art is that when chorion villus sampling is indicated it is performed by the transcervical route at 8–12 weeks and by the transabdominal route at 10–12 weeks. However, the normal genetic counselling amniocentesis when liquor rather than chorion is sampled, is performed ideally at 16 weeks. Summary: Chorion villus sampling was performed transcervically on 84 patients and transabdominally on 126 patients. Two of 4 (5%) spontaneous abortions in the transcervical group were complicated by uterine infection. Five (4%) spontaneous, abortions in the transabdominal group were uncomplicated by infection. The results support the contention that the transabdominal method may be safer and that the procedure related fetal loss rate is similar to that following amniocentesis. Copyright © 1990, Wiley Blackwell. All rights reserved