Current trends in human IVF and other assisted reproductive technologies.

The new reproductive technologies such as IVF, GIFT, ZIFT, and micromanipulation have had a profound influence on the therapeutic and diagnostic management of infertility, and in turn have resulted in better understanding of human fertilization and embryo development. While the clinical pregnancy rates in GIFT and ZIFT procedures are comparable to the natural fecundity in the population at large, pregnancy rates in IVF have been generally lower. Further investigations should be directed to improve the implantation rates, and to develop better controlled methods of multiple follicle development. Although more studies are needed, a recent report of potential utilization of nonstimulated oocytes for donor programs as well as IVF-cryopreservation was a promising new development (Cha et al. 1989). Other exciting prospects on the horizon are the possibilities of gene transfer for the treatment of certain genetic diseases and diagnostic applications of embryonal biopsy. These new technologies have also generated serious ethical and legal issues. Any ethical or legal guidelines affecting new reproductive technologies should be developed to protect all participants only when the need for regulation is clear. Ethical guidelines and appropriate legislations with contributions from the medical and scientific community are gradually being established worldwide.