Transabdominal and transcervical chorionic villus sampling: efficiency and risk evaluation of 2,411 cases.

Efficacy and risks of transcervical and transabdominal chorionic villus sampling (CVS) methods were evaluated in 1,501 and 910 cases, respectively. We reported a success rate of more than 99% for both sampling procedures and obtained an adequate amount of chorionic tissue in more than 96% of cases on the first attempt. However, the transcervical method was more difficult to learn and was contraindicated by a higher number of unfavorable clinical and anatomical conditions. Transabdominal sampling proved to be a less time-consuming procedure and could also be used after the 12th week of gestation. Bleeding/spotting (10.1%) and uterine cramping (2.5%) were the most frequent early complications following transcervical and transabdominal sampling, respectively. Uterine infection was rare (0.13%) and was reported only after cervical aspiration. No significant effects on fetal growth, preterm delivery, placenta disorders, congenital defects, and perinatal mortality following transcervical and transabdominal sampling, and for both procedures total fetal loss rate was less than 4%. This experience suggests that transabdominal needle sampling is the method of choice; however, transcervical aspiration appears more likely to succeed in a limited number of well-defined conditions.