Chromosome abnormalities identified in 347 spontaneous abortions collected in Japan.

Objective: We determined the incidence of specific chromosome abnormalities in this Japanese population so that comparisons could be made to the incidence of chromosome abnormalities reported for other populations.

Methods: A total of 423 cases of products of conception aborted spontaneously were collected for cytogenetics analysis from various medical sites located in Japan. The cytogenetic results, along with clinical information including gestational age at the time of the miscarriage and maternal age, were compiled in a database.