Prevalence of chromosomal aberrations in Mexican women with primary amenorrhoea

Primary amenorrhoea refers to the absence of menarche by the age of 16–18 years in the presence of secondary sexual characteristics, and occurs in 1–3% of women of reproductive age. To study the prevalence of chromosomal abnormalities and the different options available for clinical management of women in Mexico with primary amenorrhoea, a cross-sectional study was conducted in 187 women with primary amenorrhoea referred from Department of Reproductive Medicine of Morones Prieto Hospital, IMSS in Monterrey, Mexico during 1995–2003. Peripheral blood lymphocytes were cultured for chromosomal studies by the standard methods. Numerical or structural abnormalities of the sex chromosome were found in 78 women (41.71%). These women were classified into four categories: X-chromosome aneuploidies (22.99%: 12.83% pure line and 10.16% mosaicism association with a 45,X cell line); presence of chromosome Y (10.70%); structural anomalies of the X chromosome (4.28%); and marker chromosomes (3.74%). In conclusion, the prevalence of chromosomal abnormalities in Mexican women with primary amenorrhoea is within the range (24–46%) reported in world literature. Chromosomal analysis is absolutely necessary for appropriate clinical management of these patients.