Microinsemination of Human Oocytes
The severely oligozoospermic padent usually has a combination of multiple sperm defects1 with very poor chances of spontaneous conception. In vitro fertilization (IVF) with embryo replacement (ER) has also not improved pregnancies in such cases. De Kretser and co-workers reported that when there is a combination of three or more defects in the semen analysis, fertilization in vitro diminishes to less than 8.0%.2 Even tubal embryo transfer (TET),3 otherwise known as pronuclear stage transfer (PROST) or tubal embryo stage transfer (TEST),4 does not offer hope for such patients as their spouses1 oocytes still need to be fertilized before the transfer of embryos into the fallopian tubes. Zona drilling to assist sperm penetration when first described5 also offered hope for such patients but clinical trials using the technique did not produce any pregnancy.6 Moreover, zona drilling with acid Tyrode’s solution has been found to affect the meiotic process, probably by anaphase II arrest. 7 Recently, Cohen and co-workers described a new approach in which the zona of oocytes were partially dissected using force only via the micromanipulator (partial zona dissection, PZD).8 Using this technique, they have reported three pregnancies,9 which have since increased to six.
KeywordsZona Pellucida Human Oocyte Sperm Transfer Perivitelline Space Sperm Density
Unable to display preview. Download preview PDF.
- 1.World Health Organization Task Force on the Diagnosis and Treatment of Infertility. Towards more objectivity in diagnosis and management of male infertility. (Prepared by F. H. Comhaire, D. de Kretser, T. M. M. Farley, and P. J. Rowe), Int. J. Androl., Suppl.7:l (1987).Google Scholar
- 2.D. M. De Kretser, C. A. Yates, J. McDonald, J. F. Leeton, G. Southwick, P. D. Temple-Smith, A O. Trounson, and E. C. Wood, The use of in vitro fertilization in the management of male infertility, in: “Gamete Quality and Fertility Regulation”, R. Rolland, M.J.U. Heineman, S.G. Hillier, and H. Vemer, eds., Excerpta Medica, Amsterdam (1985).Google Scholar
- 3.P. C. Wong, A. Bongso, S. C. Ng, C. L. K. Chan, L. Hagglund, C. Anandakumar, Y. C. Wong, and S. S. Ratnam, Pregnancies after human tubal embryo transfer (TET): a new method of infertility treatment, Singapore J. Obstet. Gynecol., 19:41 (1988).Google Scholar
- 10.S. C. Ng, T. A. Bongso, A. H. Sathananthan, and S. S. Ratnam, Micro- manipulation: its relevance to human IVF, (Review), Fertil. Steril.,(Feb. 1990).Google Scholar
- 13.S. C. Ng, S. S. Ratnam, H. Y. Law, W. R. Edirisinghe, C. M. Chia, M. Rauff, P. C. Wong, S. C. Yeoh, C. Anandakumar, and H. H. V. Goh, Fertilization of the human egg and growth of the human zygote in vitro: the Singapore experience, Asia-Oceania J. Obstet. Gynecol., 11:533 (1985).Google Scholar
- 18.A. H. Sathananthan, S. C. Ng, A. O. Trounson, T. A. Bongso, A. Laws- King, and S. S. Ratnam, Human micro-insemination by injection of single or multiple sperm: ultrastructure, Human Reprod., In press (1989).Google Scholar
- 20.B. Kjessler, Facteurs genetiques dans la subfertile male humaine, in: “Fecondite et Sterilite du male. Acquisitions recetes”, Masson, Paris (1972).Google Scholar
- 23.T. A. Bongso, S. C. Ng, S. S. Ratnam, A. H. Sathananthan, and P. C. Wong, Chromosome anomalies in human oocytes failing to fertilize after insemination in vitro, Human Reprod., 3:645 (1988).Google Scholar
- 27.S. E. Lanzendorf, J. F. Mayer, J. Swanson, A. Acosta, M. Hamilton, and G. D. Hodgen, The fertilizing potential of human spermatozoa following microsurgical injection into oocytes, 5th World Congress on IVF and ET, Program Supplement, AFS, 65 (1987).Google Scholar