[Methods of chorion sampling for prenatal diagnosis in the 1st trimester of pregnancy. Report of experiences].

Report on first experiences in chorionic villi sampling in the first trimester of 131 pregnancies. Chorion biopsy was performed just before termination of pregnancy in the 9th-11th week of gestation. Of 3 tested biopsy methods we found the biopsy with a flexible forceps under guidance of real-time ultrasound to be the best.