After 80 years of research into male contraceptives, the prospect of a viable alternative to condoms and vasectomies is finally on the horizon. Why has it taken so long? And was the wait really necessary? Sceptics argue that further birth control options for men are unnecessary considering the number of contraceptive products available for women. However, the Guttmacher Institute and United Nations Population Fund published a study in 2003 which estimated that the unmet need for contraception is between 137 and 200 million women globally. This suggests that existing products simply aren’t satisfactory, either in terms of patient experience or accessibility.
For the uninitiated, here’s a brief timeline of male contraceptive research. In the 1920s the physiological basis for inhibiting sperm production with hormonal intervention was first discovered in rats. The possibility of doing so in humans was demonstrated in the 1930s, but the federal ban on contraception in the US, that existed from 1873 until 1938, rendered it commercially non-viable. In the 1990s the WHO conducted studies on 670 men across 10 countries proving that variations on this method are both effective and safe, spurring interest in developing male contraceptives across the pharmaceutical industry.
In contrast, the pharmaceutical industry continued widespread research and development of female contraceptive products and new products are still regularly released to this day. In the early 1950s Gregory Pincus, co-inventor of the first oral contraceptive pill for women, and Margaret Sanger met at a dinner party, where she convinced him to help her in her quest to create the first contraceptive pill. By 1960 the pill was approved by the FDA for contraceptive use, swiftly followed by the first IUDs in 1968, the implant in 1990 and the morning after pill in 1999.By the mid 2000s, though, major pharmaceutical companies such as Bayer, Wyeth and Organon discontinued their male birth control R&D programmes, stating that the regulatory burden to prove rates of efficacy and safety similar to those achieved by the equivalent female products was causing them to incur costs which they could not justify.
Here’s the problem. Regulatory bodies require that male contraceptive products display similar efficacy, side-effect severity, and fertility recovery rates to products which exist for women. The first female oral contraceptive pill hit the market 40 years before the development of the first male contraceptive products even began. Scientific advances build upon one another and the timescale and population size limitations of clinical trials are mitigated significantly by widespread commercial use. Female contraceptive methods have accumulated a body of knowledge and a vast patient population database on a global scale due to their mass popularity. Asking the burgeoning field of male contraceptive products to compete against this is like asking Muhammad Ali to fight a 17-year-old World Cadet Champion; a fight the pharmaceutical companies who attempted to tackle the market in the mid-2000s were all too aware of.
It’s also unusual for medical treatments for two different conditions to be held to exactly the same standard. They often wildly diverge in their risk-benefit ratio. When treatment options are few and far between, patients and doctors believe it is justifiable to take on high risks. Indeed, this approach indicates that the regulatory authorities view both male and female contraception as different solutions to the same problem: female pregnancy. Such a view reflects an outmoded conception of birth control as a method of family planning, which is out of place in today’s world where participation in casual sex is enjoyed by all genders. A more modern view would see male and female contraception as distinct solutions which temporarily terminated the fertility of the individual, empowering them to insulate themselves against the physical, financial, and emotional risks of unwanted pregnancy. If the revised view were adopted by regulatory authorities the risks and benefits of new male contraceptive methods would be measured against the methods which currently exist: condoms, vasectomy, and pulling out.
So how do up and coming methods compare against those which are currently available? Condoms have a theoretical success rate of 98% but human error means the observed rate is closer to 82%, meaning 18 women relying on condoms exclusively will get pregnant out of every 100. The pull-out method has a theoretical success rate of 96%, but an observed rate of 78%. These rates are knocked out of the park by emerging methods such as RISUG, a reversible non-invasive vasectomy, which has a 98% observed success rate. The only 100% successful method currently available for men is vasectomy, which causes chronic testicular pain in 15-33% of patients, has only a 55% chance of reversal in the first 10 years, and is a costly and invasive procedure, rendering it non-viable for many men.
As no male contraceptives have reached end-stage clinical trials yet, it is impossible to directly compare the risks to those of a vasectomy. In 2016, trials for an injectable hormonal birth control for men were controversially terminated on the basis of adverse side effects, despite 75% of the men involved wanting to continue. Women in the media have criticised men for being incapable of enduring the side effects women face every day. Although the side effects experienced by the men in the trial are likely greater than those faced by women on modern contraception, the original oral contraceptive pill ‘Enovid’ was trialled on psychiatric inmates involuntarily because the side effects were so severe that it was difficult to obtain enough participants to partake in the trial. By the time the first reports of women taking the pill experiencing blood clots and pulmonary embolisms arose in 1961, over a million women had been on the drug. The FDA have since refuted claims of negligence, stating: ‘Had the drug been ineffective, or even less effective than mechanical contraceptives already available (condom and diaphragm), then its safety would have been difficult to establish. The Pill met the law’s safety requirement precisely because it was so effective. Understood in this context, the Pill was safer than other contraceptives on the market.’ They were right, and the same logic should be applied to the male contraceptive pill: if it’s better than the alternatives for male contraception, research into it should continue.
By Richéal Ni Laoghaire – Science Editor