Do male contraceptives exist? See what is already known about the method

The male contraceptive may already be a reality in the coming years. Called RISUG (acronym in English for Reversible Inhibition of Sperm Under Control), the method is in the study phase, with expected release in 2023🇧🇷

With the focus on inhibiting the ovulatory process since its inception, today, only contraceptive options aimed at the female audience can be found. However, the large hormonal burden and side effects of contraceptives led to new alternatives being debated.

So research led by biomedical engineer Sujoy Guha is focused on creating a male contraceptive that not only inhibits sperm production, but can also block HIV transmission.

How it works?

Fernando Meyer, urologist, explains that RISUG was formulated as an occlusive polymer (macromolecules) to sterilize individuals by single injection🇧🇷 Furthermore, the technique can be reversed at any time after vessel occlusion.

The drug is injected in a gel format directly into the region responsible for carrying the sperm to the semen. After 72 hours, RISUG causes a type of “ionic stress” in spermatozoa, which causes a change in pH and a series of changes in their structure, making them unable to fertilize eggs🇧🇷

“That is, we inject this substance into the vas deferens (the channel that takes sperm from the testicle into the prostate, where it mixes with sperm and is ejaculated). When the man has sexual intercourse, this sperm inside the vagina will move up through the cervix until it fertilizes the egg. And this substance injected into this channel (which is the channel we cut to perform the vasectomy) has a positive charge”, says the doctor.

Normally, sperm has a negative charge. That way, the substance will neutralize it, leaving it immobile. “He will not be able, when ejaculated, to progress into the uterus and reach the tube to carry out fertilization. This is the mechanism of action: it is a substance that goes neutralize the spermleaving it immobile so that it is unable to carry out fertilization”, explains Fernando.

Method effectiveness

So far, RISUG is in the phase III of studies – considered the final phase. During the process, Fernando says that six months after the start of the tests, about 6.7% of the individuals had azoospermia (absence of spermatozoa in the semen) after the injection of the gel.

“The contraceptive efficacy was 99.02% with 0.3% failure of the method and 0.98% of general failure in the effectiveness of the medication”, he says. The birth control pill, for example, if used absolutely correctly, is 99.8% effective.

Because it is still being studied, there is no defined age range or restrictions for the use of contraceptives. In addition, despite being a potential antiretroviral drug, deeper analyzes are still needed on the action of the injection against STIs (Sexually Transmitted Infections).

arrival at the market

While promising, further testing and analysis is still needed before RISUG is released to the public. Still, there are health professionals who question the effectiveness of the method, which may lead to specific research being carried out in each country.

“Since it is still in clinical studies, we have no plans to arrive in Brazil definitively. Bearing in mind that all new drugs and substances need to pass through the ANVISA”, emphasizes Fernando.