In utero chorionic villus sampling at the time of diagnosis of intrauterine fetal death is compared with more traditional use of cultured fetal skin, products of conception, or amniocentesis. A total of 102 specimens from early fetal losses were evaluated for success in karyotyping and chromosomal results. We found postmortem chorionic villus sampling is technically possible, offers the highest likelihood of getting a cytogenetic result, and is a rapid, reliable, and safe technique. The extraembryonic component of intrauterine fetal deaths appears to remain viable and continues to grow long after the embryo has died. Samples obtained at the time of diagnosis of fetal death offer the greatest changes of successfully obtaining a karyotype. The incidence of chromosome abnormalities associated with fetal loss, particularly trisomies, is higher than previous data suggested.