Studies on gamete manipulation (IVF-ET, GIFT, IVF-ETR and Micromanipulation)

点击翻译按钮获取中文摘要

Superovulation with GnRHa-HMG, ultrasound guided transvaginal oocyte recovery and flexible embryo transfer made it possible to perform IVF-ER on outpatient basis avoiding working on Sunday. The overall pregnancy rate of IVF-ET was 29.0% (357/1231) per ET. IVF-ET was effective for infertility of various kinds of etiology except for male factor infertility with abnormal sperm fertilizing ability (ZSPT*30%). The pregnancy rate was not affected by the day of embryo transfer up to 3 days after insemination. GIFT was applied-with great expectancy, especially for patients with male factor infertility. However, the results were rather disappointing : the pregnancy rate of patients, with abnormal ZSPT (* 30%) was only 7.8%. IVF-ETR was very effective for patients with sperm immobilizing antibody who achieved 56.3% of pregnancy rate per ETR.Clinical feasibility of assisted fertilization by micromanipulation was assessed using non-fertilized oocytes in IVF programme. Both zona piercing and subzonal insertion were safe and efficacious. However, zona drilling with acid solution caused significant damage on the vitelline membrane. Fertilization after sperm microinjection was very poor, and electron microscopic study revealed that the process of pronuclear formation was arrested at stage II in some oocytes. Chemical or electrical activation might be necessary for full developement of pronuclei and subsequent normal cleavage.