Recent headlines have heralded promising scientific advances in the production of a male contraceptive pill.
But is a male once-daily pill really just around the corner, and what would be the effects of men and women sharing responsibility for birth control?
The elusive pill for men has been within scientists’ sights for decades.
So far, the only means of male contraception are condoms, which can fail up to 18 percent of the time if worn incorrectly, or vasectomies which are complicated to reverse.
But in 2018 two clinical trials have made waves in the field.
In March, US researchers reported “promising results” from their trials of a hormonal pill called dimethandrolone undecanoate, or DMAU.
DMAU is similar to the female contraceptive pill as it contains a mixture of hormones: an androgen such as testosterone, and a progestin.
The drug was tested on 83 men aged between 18-50 for 28 days.
The study found DMAU successfully blocked the hormones required for sperm production and, importantly, caused no significant adverse effects to the men’s mood or libido.
However, the study did report side effects of weight gain of between three to nine pounds and a small change to cholesterol levels.
Still, the study has been hailed as a major step forward in the development of a once-daily male pill.
In a separate US study published in April, a male contraceptive pill containing a compound known as EP055 was successfully tested in male macaques.
When EP055 was infused, it effectively turned off the monkeys’ sperm’s ability to swim, significantly limiting the likelihood of fertilisation.
Again, none of the subjects suffered side effects.
And 18 days after being given the EP055 compound, the macaques’ sperm showed signs of complete recovery, suggesting the process is reversible. All promising stuff.
Larger, long-term studies are needed to address potential side effects.
So with these scientific advances, could a pill soon be on the shelves that would give men more options and alleviate the burden of birth control on women (most female contraceptive pills can cause side effects including weight gain, erratic moods and nausea).
Researchers behind the macaque study say it is unclear when EP055 in pill form may be available for human use.
And though the DMAU study showed some success in humans, the sample size was small and was only a month long.
Research team member Dr Stephanie Page from the University of Washington acknowledged that “larger, long-term studies are needed to address potential side effects” and that this was a “very small study and there is still a lot of work to be done”.
However a trial testing DMAU this time on 100 men over a three-month period is currently underway.
Scientists have been trying to come up with a male contraceptive pill for decades, but the research area is fraught with challenges.
It is unfair to discredit a whole gender as not being trustworthy enough to take that responsibility
The greatest is that it is harder to suppress sperm, of which men produce millions per day, than it is the one egg women produce per ovulation cycle.
And some previous male contraceptive studies have resulted in worrying side effects: in 2016 20 men dropped out of a trial for an injected male contraceptive, after reporting acne, loss of libido and depression.
Then there is the question of whether men would want to take a contraceptive pill, especially given some of the unpleasant symptoms associated with equivalent female oral tablets.
But researcher Dr Arthi Thirumalai who worked on the DMAU trial points to survey data showing men were very interested in taking responsibility for birth control.
“It is unfair to discredit a whole gender as not being trustworthy enough to take that responsibility, when they are specifically telling us otherwise,” she said.
Another question some commentators have raised, is would women want to outsource responsibility over birth control?
For many couples though, a male pill could be a huge moment: it would mean more options and the opportunity for equitable sharing of responsibility.
Over the decades headlines have frequently touted a revolutionary male pill as just around the corner, but many previous studies have fallen short; now scientists appear to be closer than ever to achieving it, but it still may be years before, if ever it appears on pharmacy shelves.
For women who struggle with side effects of years on the pill though, it is a tantalising prospect.