Complete trisomy 15 is a lethal abnormality and thus trisomy 15 detected in a normally developed embryo at a 10-12 week CVS sample is usually confined to placental tissues. Trisomy 15 was found in 34/126465 (0.027%) of CVS samples from the ‘ Collaborative Research on Mosaicism in CVS’. We report on a fetus with 47,XX,+15 chromosome abnormality detected on chorionic villus sampling (CVS). The pregnancy was terminated at 10 weeks of gestation and fetal tissues showed a karyotype 47,XX,+15. In this case, parents of karyotypes were normal. Trisomy 15 conceptions are usually aborted spontaneously in the first trimester of pregnancy. The longer survival of this fetus is most probably the result of a chromosome 15 loss from the trisomic zygote. Further investigation is needed to elucidate mechanisms that might prevent normal embryogenesis but evade detection by the cytogenetic techniques used in the present study.