A review panel stopped a previous study on a male birth control shot due to side effects. However, new research and ongoing clinical trials are investigating several other methods of male contraception.
When scientists developed the birth control pill in the 1950s, it empowered women to take control of their fertility.
However, birth control options for men have remained limited.
Although researchers investigated a male birth control injection in the late 2000s, they stopped the study due to adverse effects.
Halting the study led to news reports suggesting that men couldn’t handle the side effects. However, a review panel found the risks to the study participants outweighed the potential benefits.
Still, research involving other male birth control methods is currently underway, meaning birth control options for men might be available in the near future.
The ability to control fertility changed dramatically with the advent of the female birth control pill in the 1950s. Although scientists have investigated similar options for men, interest in developing a male version of the pill has remained relatively low.
Recently, public interest in male birth control options like the pill has increased. This is likely due to the June 24, 2022, US Supreme Court decision to overturn Roe v. Wade — legislation that made abortion a federal right in the United States.
However, because a male birth control pill also contains hormones like the female version, acceptance of this method among men has come into question.
Yet, according to a multinational survey, overall acceptance of hormonal male fertility control (MFC) was high, with around 28–71% of male survey participants expressing the willingness to use this type of birth control method. So, contrary to popular belief, it seems that men are interested in using hormonal contraceptives — if they become available.
Currently, there are only two options for male birth control — condoms and vasectomy. Condoms are about 98% effective if used correctly, while a vasectomy is more than 99% effective at preventing pregnancy. However, a vasectomy is a surgical procedure and is considered a permanent birth control option. And, although they can be reversed, success isn’t guaranteed.
This lack of options leaves plenty of room for new male contraceptives to take the stage. But, so far, scientists are still working on various options. Some are showing promise, while others have experienced a fair share of trials and tribulations, including one study that ended early because of adverse side effects.
What happened to the male birth control shot?
A study conducted between 2008 and 2012 involving hormone injections created a slew of internet chatter when scientists halted the research due to side effects. A news report suggested that the study was stopped due to male birth control side effects similar to those experienced by females taking the pill — suggesting, “men can’t handle the side effects women face daily.”
However, according to the study, a Research Project Review Panel (RP2) found the risks to the study participants outweighed the potential benefits. They also expressed concerns about adverse effects, including pain at the injection site, mood changes, depression, and increased libido.
Other adverse outcomes possibly related to the study were:
- One case of depression
- One case of intentional paracetamol (Tylenol) overdose
- One case of tachycardia with paroxysmal atrial fibrillation
The study also reports one death by suicide. However, the scientists later determined it was unrelated.
Despite these effects, about 80% of the male participants indicated that they were satisfied with this birth control method.
Are other male birth control options in the works?
Scientists are working hard to develop safe, effective birth control options for men. However, they are all in the experimental or clinical trial stages.
Here are some of the male birth control options that show the most promise:
One non-hormonal option under investigation is a compound called YCT529, which inhibits retinoic acid receptor alpha (RAR-α) — a protein associated with sperm formation. When scientists gave oral doses of YCT529 to mice for four weeks, it significantly reduced the rodent’s sperm counts. It was also 99% effective in preventing pregnancy and had no apparent side effects. Moreover, fertility in the mice returned 4–6 weeks after discontinuing YCT529.
DMAU and 11β-MNTDC
Male birth control pills that contain dimethandrolone undecanoate (DMAU) or 11β-MNTDC are also currently under investigation as hormonal birth control candidates for men. These medications suppress testosterone leading to reduced sperm counts. So far, experiments suggest that these medications appear to lower testosterone without unwanted side effects. However, since studies are still active, it’s unclear when these pills might be available to men.
Not a medicine but more like a medical device, ADAM is an implantable gel injected into the sperm-transporting tubes attached to the testes (vas deferens). Once the gel is in place, it blocks sperm from leaving the testes. After about a year, the gel dissolves, making it a temporary form of birth control. Clinical trials on the safety of ADAM began in 2021, with an estimated completion date of June 2025. So, it’s not known when this method could be available.
Reversible Inhibition of Sperm Under Guidance (RISUG) is also considered a medical device like ADAM. It’s a polymer gel injected into the vas deferens that damages sperm as they pass through. So far, research suggests it’s around 99% effective in preventing pregnancy. Although not studied in the US, RISUG is in Phase-III clinical trials in India.
Another option currently in clinical trials is NES/T, a topical gel containing hormones. This gel is applied daily on the shoulders and absorbed into the skin. It contains Nestorone, which is a drug that lowers sperm counts. It also has testosterone to help offset the side effects of Nestorone. Presently, researchers expect to wrap up the clinical trials by December 2024.
Someday soon, men might have a similar variety of birth control options available to them as women. Having more options can empower men with the ability to control their fertility. But for both men and women, deciding which method to use is a personal choice that’s dependent on many factors.
Ultimately, when choosing a birth control method, it’s best to talk with a healthcare provider to learn the risks, potential side effects, and effectiveness of the currently available options.