Chorionic villus sampling: Improved method for preparation of karyotypes after short-term incubation

Abstract
A method for the isolation and trypsin‐Giemsa banding of metaphases obtained after short‐term incubation (48 h) of cytotrophoblast cells from chorionic villus sample is described. A new slide‐making instrument, developed expressly to enhance the spreading of chromosomes from metaphases released from small tissue pieces, is responsible for the increase yield of analysable metaphases in this protocol.