Chorionic villus sampling (CVS). Randomized study of efficacy of two transcervical biopsy methods: aspiration canulas...

A randomized study of two transcervical biopsy methods was performed. One method involved the use of an aspiration catheter and the other a tissue biopsy forceps. 120 chorionic villus samplings were performed in 30 patients. The percentage of success in taking biopsies and the resulting number of karyotypes were identical in both groups. The amount of removed trophoblastic tissue was greater when the forceps was employed. When the aspiration catheter was used, a sufficient amount of trophoblastic tissue was obtained for karyotyping purposes. It was easier to insert the aspiration catheter than the forceps. The echogenicity of the catheter and forceps were identical. The aspiration catheter has two advantages. Firstly, it is malleable and fits to the anatomy of the cervical canal and the site from which the biopsy is to be taken. Secondly, it is disposable.