We report the ultrasound, cytogenetic and morphologic findings in a case of
trisomy 10 mosaicism prenatally detected by chorionic villus sampling (CVS
). CVS sampling was carried out at the 13th week of gestation because of ul
trasound diagnosis of hydrops fetalis and hygroma colli. Trisomy 10 mosaici
sm was diagnosed in cells from the cytotrophoblast (short-term culture) and
the chorionic villus core (long-term culture). Fetal mosaicism was confirm
ed after termination of pregnancy in umbilical cord cells, placenta and fet
al skin fibroblasts. Copyright (C) 1999 John Wiley & Sons, Ltd.