How common is germinal mosaicism that leads to premeiotic aneuploidy in the female?

ConclusionsOocytes with premeiotic errors will significantly contribute to the high level of preimplantation and prenatal death. Data so far available suggests that, depending upon the maternal age, up to 40% of aneuploidy that is present in oocytes at the end of meiosis I may be due to germinal mosaicism.
Source: Journal of Assisted Reproduction and Genetics - Category: Reproduction Medicine Source Type: research