The 2014 annual meeting of the Society for the Study of Reproduction began, somewhat incongruously, with a discussion of contraception. With the global population set to top 8 billion in a little more than a decade, clinicians, public-health researchers and some private funders see a pressing need to support work on new contraceptive methods — and to get existing methods into the hands of those who want them.

Contraception is unique among medical interventions for the wide variety of benefits it offers, says Anna Glasier, a researcher in contraception and public health at the University of Edinburgh, UK. In addition to reducing the burden of overpopulation, it has improved health, reduced infant and mother mortality and empowered women — but it is used at vastly differing rates from country to country.

Researchers generally suspect that the more educated the women, and the higher they rank in other socioeconomic factors, the more demand they will have for contraceptives. But when women in rural Bangladesh were offered high-quality contraceptive advice and a range of options in the 1970s to 1990s, their use of contraceptives increased from 5% to 45% — dramatically reducing the birth rate and mother and infant mortality.

In developed countries such as the United States — where up to half of all pregnancies are unwanted or mistimed — even people with access to treatments such as oral contraceptive pills often fail to use them properly. A 2010 study of women in Boston, Massachusetts, found that daily text-message reminders to take the pill did not do much good.  “You begin to think you’re banging your head against the wall,” says Glasier.

Pick and choose
With that in mind, researchers are seeking to increase the array of choices available, hoping that women will be able to find methods more suited to their lifestyles. One non-surgical approach uses polidocanol, a drug that has been approved by the US Food and Drug Administration for treating of varicose veins, but that can also be used to induce scarring in the fallopian tubes, keeping eggs from reaching the uterus. Jeffrey Jensen, a reproductive-medicine specialist at Oregon Health & Science University in Portland, has been testing the approach in monkeys. He says that polidocanol could one day be a cheap and easy option for women who want to curtail their fertility permanently.

Scientists at the meeting, held in Grand Rapids, Michigan, were less cheerful about the prospects of developing a hormonal contraceptive for men. Christina Wang, a reproductive-health researcher at the University of California, Los Angeles, is working to develop such a pill by combining a progestin steroid with testosterone. But she says that pharmaceutical companies' interest in such treatments has cooled over the past decade.

Wang is still optimistic that men — particularly single men — would be interested in a safe, effective way to control their fertility. But as Jensen points out, risks from an unplanned pregnancy are simply not as clear and present for men as they are for women.

This article is reproduced with permission and was first published on July 23, 2014.