The past 50 years have seen little change in male contraception, compared to the range of options available to women. The only options available to men are condoms and vasectomies.
Ongoing research
There are many ongoing research projects that look at different methods of male contraceptive. Researchers involved in the projects are optimistic that a safe, effective method of male contraception will be a reality by 2015.
However, researchers involved in earlier projects made similar claims. One commentator recently said: "We’ve been hearing that a male contraceptive pill is 'five or 10 years away' for the last 25 years."
Types of research
There are two main areas of research in male contraception:
Hormonal contraception: where synthetic hormones are used to temporarily stop the development of healthy, child-bearing sperm.
Non-hormonal methods: where other techniques are used to stop healthy, child-bearing sperm, entering a woman’s vagina.
Hormonal contraception
In fertile men, new sperm cells are continually being created in the testes. This process is spermatogenesis.
Spermatogenesis is triggered by the hormone testosterone. Another hormone, gonadotropin causes the body to release high levels of testosterone in order to produce new sperm cells.
The goal of hormonal contraception research is to find a way of temporarily blocking the effects of gonadotropin and testosterone so that the testes stop producing healthy sperm cells, without lowering testosterone levels to such an extent that would trigger side effects, such as loss of sexual desire.
One way this may be achieved is by giving men a synthetic version of testosterone. The synthetic testosterone would stop the body producing natural testosterone, meaning that no new sperm cells would be produced while at the same time, keeping testosterone levels in the body high enough to prevent side effects.
There are a number of trials in several countries that are looking at the effectiveness and long-term safety of hormonal contraceptives for men.
Non-hormonal contraception
Many of the non-hormonal methods of contraception currently being studied, involves the vas deferens.
The vas deferens is the tube that sperm pass through on their way to the penis, and it is this tube that is cut during a vasectomy.
One promising avenue of research is a technique called Reversible Inhibition of Sperm Under Guidance (RISUG). During this technique, a synthetic gel is injected into the vas deferens. The gel then coats the lining of the vas deferens and kills any sperm as they pass by.
The gel stays in place permanently until a man decides he wants to have children. Then the gel can be washed out using another injection.
A variation of this technique is the Intra Vas Device (IVD). IVD involves injecting a silicone plug into the vas deferens, which can be removed later.
Initial results of RISUG and IVD are promising, but further research is needed to assess the long-term effectiveness and safety of both techniques.