Retrospective and Prospective Epidemiological Studies of 1500 Karyotyped Spontaneous Human Abortions

Chromosome abnormalities identified in 347 spontaneous abortions collected in Japan

“…In conclusion, the overall profile of chromosome abnormalities detected in the present study is similar to the distribution in previous reports 11,12 . Our data appear to support the hypothesis 7 that there are no ethnic differences between samples from the Japanese population and those from other countries.…”

Ultrasound prediction of risk of spontaneous miscarriage in live embryos from assisted conceptions

“…The biological explanation includes the fact that meiotic non‐disjunction during oogenesis is more frequent in older mothers and their offspring are at increased risk of trisomies 13, 16, 18 and 2112, 13. The incidence of chromosomal abnormalities in spontaneous abortuses during the first trimester has been reported to be as high as 61.5%14. In the current multivariate analysis, increasing maternal age demonstrated a trend towards an increased risk of subsequent miscarriage as expected (OR, 1.14; 95% CI, 1.03–1.27).…”

Embryo Aneuploidy Screening for Unexplained Recurrent Miscarriage: A Minireview

“…It is well known that a negative selection exists against chromosomally abnormal offspring in nature. As a result of early preselection and subsequent pregnancy losses, the incidence of chromosomal abnormalities decreases with the advancing gestational age and successful pregnancy occurs in such a manner that the incidence of chromosomal abnormalities in live births is 0.6%, 1 whereas the incidence in spontaneous abortions is around 50–70% 8–12 . In chorion villus biopsies, it has been demonstrated that this percentage might even reach 83% 13 .…”