Reproductive possibilities for infertile couples: present and future

Infertility affects at least 14% of the reproductive population worldwide. Modern technology can provide genetically related offspring to 80% of couples seeking treatment, and pregnancy to a further 10-15% using donated gametes. However, that only a small proportion is able to acquire suitable treatment, even in the West, highlights the social, economic and political difficulties surrounding available resources for assisted conception technology. Before 1992 approximately 95% of severe male-factor infertility cases were offered sperm donation - unacceptable in many cultures. Since the development of intracytoplasmic sperm injection (ICSI), 90-95% of male-factor cases can now be offered the chance of their own genetic offspring. The use of egg donation and of surrogacy further expands opportunities for infertile couples to have children. In the former the recipient gestates and delivers her child, albeit genetically unrelated to herself, whilst in the latter the commissioning couple can have their genetic offspring via host surrogacy These technologies remain ethically challenging. Developments in embryology technology have helped couples whose problem is one of implantation rather than conception, and this includes assisted hatching and zygote/embryo repair. The alliance of such technologies to the development of molecular genetics permits the biopsy of an eight- to ten-cell embryo for chromosome/genetics analysis on the extracted cells. This procedure has both social and economic advantages and makes it possible for couples to refrain from embarking on a pregnancy should the embryo carry a feared hereditary disorder. More recently, techniques to preserve germ cells, both mature and immature, and the potential in prepubertal male cancer sufferers for ipsigeneic germ cell repopulation offer considerable opportunity to preserve the fertility of these boys. The technique of oocyte grafting after cryopreservation provides similar opportunities for females of all ages. The inherited disease of mitochondrial deoxyribonucleic acid (DNA) cytopathies, passed on through the maternal line via the egg cytoplasm, poses serious health risks to offspring, including epilepsy, deafness, blindness and muscular atrophy. Potential developments in embryo/zygote micromanipulation could provide the opportunity to preserve the genetic complement of the parents, while protecting the future offspring from diseased cytoplasmic mitochondria. Similar technology might help those couples who are infertile as a result of habitual miscarriage, rather than any problem with conception and implantation per se. Hence, in the future: in vitro fertilization (IVF) and embryology technology will not only provide children for the subfertile, but will encroach on health and disease issues unrelated to infertility.