By Carmen Abbe and Alison Roxby
A clinical trial on a novel male contraceptive was recently terminated early due to participant side effects, or adverse events. Yet it is well known that many contraceptives used by women cause significant adverse effects.
Our recent paper in BMJ Sexual and Reproductive Health sought to better appreciate the risk of contraceptive adverse events. We compared adverse events experienced by women on approved hormonal contraceptives with the adverse events experienced by participants of the injectable male hormonal contraceptive clinical trial.
Worldwide, there is an unmet need for male contraception. As female methods continue to be developed, no new male methods have been developed since the condom and vasectomy. A paradigm may be developing where, despite acceptability and efficacy in clinical trials, novel male contraceptive development is stalled.
We decided to enumerate adverse events experienced by men compared to adverse events reported by women in clinical trials for the most popular hormonal contraceptives. Reviewing adverse events side by side provides a tool to understand the reality of adverse event frequency across contraceptive methods.
Remarkably, we demonstrated that comparable adverse events experienced by men occurred at similar frequencies to the adverse events experienced by women on approved contraceptive methods.
Concerning adverse events were present in both male and female contraceptive methods. These results show that there is inherent risk to be managed in the use of hormonal contraception, for both men and women. If adverse events are comparable between men and women, it is concerning that male hormonal contraceptives continue to fail in developmental stages.
The male contraceptive study under review reported that the potential risks of the contraceptive were deemed to outweigh the potential benefits, leading to the trial’s discontinuation. In female contraceptive trials, adverse events are also seen, but deemed acceptable compared to risks of pregnancy. As future research continues, we are confronted with determining how much risk is acceptable for male contraceptive methods. Through the approval of female hormonal contraceptives, regulatory agencies have provided women the ability to choose whether the risks of a contraceptive outweigh the risk of an unintended pregnancy. Men ought to have the same freedom of choice.
Women too often carry the financial and physical burdens of contraception. Male contraception provides the opportunity for all people, regardless of gender, to share control over family planning. Male contraception also gives men an overdue means to control their fertility in an effective and reversible way. Men’s interest in effective contraception should be considered in the discussion of the appropriate risks of male contraceptive methods.