[Assisted fertilization--where are we now and where are we going?]

The authors review the development of assisted reproduction, and describe the present status. The efficacy of in vitro fertilization is compared with the results of tubal surgery. A comparison is also made of the efficacy of different assisted reproductive techniques. Future aspects of assisted reproduction are discussed, with particular emphasis on the need for better understanding of the implantation process. This may reduce the need for transfer of multiple embryos, thereby decreasing risk of multiple pregnancies.