Unlike their female counterparts, today's sexually active men have few options for effective birth control: They can choose between using a condom or getting a vasectomy. Some may include the dubious "pullout" method among these choices as well.
Male hormonal contraceptives are not currently available. Research is ongoing and scientists continue to collect important findings. The current goal is to identify a male hormonal contraceptive that is effective, reversible, safe, acceptable, affordable, and available.
What about non-hormonal birth control shots?
In the United States, Vasalgel is one of the male contraceptive options furthest along in research.
Vasalgel is a long-term, non-hormonal, and reversible contraceptive polymer. The polymer is administered as an injection into the vas deferens (the tube that sperm swim through). To reverse its effects, another injection is administered to the site in order to flush out the polymer.
Vasagel has undergone animal and safety trials. Ongoing fundraising initiatives are focused on supporting future human subject clinical trials.
A similar injection, known as RISUG (Reversible Inhibition of Sperm Under Guidance) has shown equal promise over the years. The RISUG injection is currently only available to Indian men who live near study sites in India.
After consenting the man for the procedure, the clinician administers a local anesthetic, followed by an injection containing the birth control into each of the vas deferens. The Vasagel polymer sets up as gel in the Vas deferens and blocks the sperm. The RISUG gel acts first by binding to the inner walls of the vas deferens and within 1 hour, rupturing the sperm before the sperm leaves the body.
Several male contraceptive methods are in in various stages of research and development.
The United Nations World Health Organization, the University of California, the University of Los Angeles, and the University of Sydney have all conducted studies to understand the effects of hormonal injections on sperm production. The use of testosterone has shown lower sperm count without any negative effects in libido, ability to get an erection, and achieving orgasm. A testosterone derivative plus a progestin will most likely be the first hormonal contraception method for men.
Male hormonal contraception has been shown to be about 95 percent effective, reversible, and causes few side effects. However, maximum effectiveness may take up to 3-4 months. .
Gendarussa (sometimes spelled "gandarusa") is a non-hormonal, herbal contraceptive. Its active ingredient comes from the Justica gendarussa plant. It prevents sperm from fertilizing an egg via an unclear mechanism.
The team at Airlangga University in Indonesia is leading the research behind Gendarussa.
CatSper is a sperm-specific ion channel that is essential for sperm motility. A drug that could inactivate CatSPer would disable sperm and prevent fertilization of an egg.
Researchers at UC Berkeley have screened more than 50 chemical compounds to find ones that could tightly bind with CatSper. Two most promising agents are found in plants: lupeol, a compound found in mangos, grapes, and olives, and pristimerin, which comes from an ancient medicinal herb.
Epididymal Protease Inhibitor (Eppin)
In development by Eppin Pharma Inc., Eppin is a reversible non-hormonal male birth control pill. It binds to the sperm surface and inhibits sperm motility. Eppin Pharma Inc published results of a proof of concept study in primates in April 2018.
Clean Sheets Pill
A fast-acting male contraceptive, the clean sheets pill is in the early stages of development in London. It works by causing a semen-free orgasm without affecting sensation.
Additionally, the pill could potentially reduce the male to partner HIV transmission risk.
For a more comprehensive list of research still in development, check out the Male Contraceptive Initiative website.
A large portion of the delay lies in the challenges at the research and development level. For years, researchers tackled the problem by attempting to shut down the production of sperm.
Researchers are also focusing on disabling aspects of sperm. Beyond the scientific challenges, social and political factors also play a role. The success of female birth control for more than half a century reinforced for many the idea that contraception should be a woman's responsibility. Its success also diminished the need to provide an alternative, male contraceptives included.
Big pharma has withdrawn support in research and development of contraception. This may be due to concerns of potential unknown long term side effects, consistent use, cost, and differential pricing for developed and developing countries..
Collaborations amongst government, non government agencies, academia, and industry may best identify potential male contraceptives, facilitate clinical trials and regulatory approval, and ensure accessibility of approved agents..