Male contraception: another Holy Grail.

The idea that men should participate in family planning by playing an active role in contraception has become more acceptable in recent years. Up to the present the condom and vasectomy have been the main methods of male contraception. There have been and continue to be efforts to develop an acceptable hormonal contraceptive involving testosterone (T) suppression. However the off target affects, delivery of the analogs and the need for T replacement have proven difficult obstacles to this technology. Research into the development of non-hormonal contraception for men is progressing in several laboratories and this will be the subject of the present review. A number of promising targets for the male pill are being investigated. These involve disruption of spermatogenesis by compromising the integrity of the germinal epithelium, interfering with sperm production at the level of meiosis, attacking specific sperm proteins to disrupt fertilizing ability, or interfering with the assembly of seminal fluid components required by ejaculated sperm for acquisition of motility. Blocking contractility of the vas deferens smooth muscle vasculature to prevent ejaculation is a unique approach that prevents sperm from reaching the egg. We shall note the lack of interest by big pharma with most of the support for male contraception provided by the NIH.