Chromosomal analysis of meiotic stages of human oocytes matured in vitro: benefits of protease treatment before fixation.

OBJECTIVE: To modify Tarkowski's air-dry technique for mouse oocytes to develop a rapid, consistent procedure for human oocytes that enables accurate scoring of meiotic stage. DESIGN, SETTING, AND PATIENTS: Meiotically immature human oocytes, obtained after oophorectomy, were cultured for various periods and then subjected to Tarkowski's air-dry procedure (n = 104) or to our modified procedure (n = 175) that used a brief exposure to protease (20 to 40 seconds) before fixation. MAIN OUTCOME MEASURES: Air-dried oocytes were assessed for readability and for whether they contained overspread or overlapping chromosomes. In addition, discrete meiotic stages in human oocytes were identified. RESULTS: Our protease procedure significantly increased readability of air-dried oocytes (96% versus 79% readable for protease versus Tarkowski, respectively; P less than 0.001) by significantly reducing the number of preparations with either overscattered (0.7% versus 3.4% for protease versus Tarkowski, respectively, P less than 0.05) or overlapping (1.3% versus 18% for protease versus Tarkowski, respectively, P less than 0.001) chromosomes. CONCLUSIONS: Protease exposure of oocytes, combined with a modification of Tarkowski's procedure, resulted in high quality air-dries of human oocytes. This rapid and reliable procedure should have clinical application in in vitro fertilization programs for meiotic assessment of oocytes failing to fertilize.

Pure gonadal dysgenesis with microscopic ovarian streak and gonadoblastoma.

A phenotypic female with an XY karyotype and no grossly demonstrable streak gonads is described. She had a microscopic focus of gonadoblastoma developing in a 3 X 2 mm area in the region of the ovarian vessels. The case stresses the importance of a careful search of the pelvic cavity in phenotypic females with a 46, XY karyotype.