New Male Birth Control Options Are Closer to Reality

Sixty-five percent of women aged 15-49 in the U.S. currently use some form of contraception, and about 13% of women in that age group regularly take an oral contraceptive. The FDA first approved a contraceptive pill for females in 1960, and now women have a host of other methods, too – a patch, vaginal ring, injection and intrauterine implant (IUD), among others. But with no approved male birth control pills or injections available, men are limited to two main options – condoms and vasectomies – each with their own potential challenges.

Research on male contraception has been ongoing for decades, but no pill has successfully taken off … yet. However, promising clinical trials are under way on multiple methods, from the tried-and-true pill form to a topical gel. Here are the latest updates:

Pills

Hormonal contraceptives for females contain a small amount of estrogen and progestin hormones, inhibiting the body’s natural hormones and preventing pregnancy on various fronts -- stopping ovulation and making it difficult for the sperm to go through the cervix and find an egg. They can also change the lining of the womb to reduce the chance that a fertilized egg implants. While effective, hormonal contraceptives can result in side effects like weight gain, acne and headaches.

Testosterone is produced in the testes in very high amounts, which is needed for sperm production. The approach with male contraception is to inhibit sperm production. A once-daily oral option has passed the first clinical hurdles, effectively showing testosterone suppression for three months. Using progestin hormones to reduce sperm production showed to be in line with the effectiveness of taking female oral contraceptives (less than 1 million sperm per mL is the “magic number”). Work on the phase 2 trial is under way.

Researchers have seen some of the same unwanted side effects in the male hormone-based trials, so they’re also working on non-hormonal methods, like a pill that targets a vitamin A-producing protein that plays a role in cell growth and sperm formation. Human trials are slated to start this year.

Topical Gel

A new hormonal skin gel applied to upper arm/shoulders once a day showed to lower sperm count within weeks. Made from a combination of Nestorone and testosterone, the gel allows the body to absorb the hormones slowly through the skin with fewer side effects. At the end of one year trial, the participants’ sperm count bounced back to normal levels in about 16 weeks.

Injection

RISUG (reversible inhibition of sperm under guidance) is a non-hormonal, minimally invasive shot effective for up to 10 years. It has shown promising results in other countries, and in the U.S. it’s the male contraceptive option furthest along in clinical trials under the name Vasalgel. The injection is alsoreversible and appears to have no side effects.

As research continues on the development of effective male contraceptive methods, experts hope the end result is a positive impact on public health by decreasing unintended pregnancy, as well as opportunities for men to have a more active role in family planning.