Most of us are familiar with contraceptive methods for women which have had positive
results in lowering the risk of unwanted pregnancies, but now scientists have produced a
contraceptive method for men. The study was published last week, on October 27 th in the
Journal of Clinical Endocrinology & Metabolism. The study was carried out by Dr. Mario
Philip Reyes Festin, a medical officer on the human reproduction team at the World Health
Organisation in Geneva. The male birth control involves injecting the men with shots of
hormones to lower their sperm counts. Some men experienced depression as a result of the
injections so they study had to be stopped prematurely. This means that more research will
need to be done before this method of contraception can become available to men. Dr.Festin
said “Although the injections were effective in reducing the rate of pregnancy, the
combination of hormones needs to be studied more to consider a good balance between
efficacy and safety.”
Until now the only form for controlling a man’s fertility is by using condoms and
withdrawing during intercourse, these are ineffective ways of managing birth control the
researchers said. A vasectomy is another option for men but this procedure is very invasive
and often not reversible. The study involved 320 healthy men ages 18 to 45 living in seven
countries: Australia, Chile, Germany, India, Indonesia, Italy and the United Kingdom. All of
the men were in monogamous, long-term relationships with women, and none of the couples
had a condition that would prevent them from getting pregnant. The men were injected with
the hormonal shots every eight weeks, for up to a year. The injection contained a type of
testosterone called testosterone undecanoate, and a form of progestogen called norethisterone
enanthate. These combined hormones suppress the production of sperm. The men received
the hormones in two separate shots.
Throughout the first 26 weeks of the study, they were asked to use other types of non-
hormonal birth control to avoid pregnancy while the men’s sperm counts decreased. The
researchers aim was to reduce men’s sperm counts to a concentration of 1 million sperm per
milliliter of semen. A fertile man contains a sperm count of 15 million sperm per millilitre of
semen. The shots proved to be effective at reducing the sperm production in 96 percent of the
men who stayed in the study. After 26 weeks, they were told to remain on the shots for
contraception. Four men’s partners became pregnant out of the 266 men who had
participated in the study. This means that there was a pregnancy rate of about 1.5
pregnancies per 100 people who remained in the study. The reason for the pregnancies were
due to the men’s sperm production not been effectively reduced by the hormone injections.
The female contraceptive pill is not always a reliable method either. During an average year,
about 9 percent of women using the pill get pregnant according to the Centre for Disease
Control and Prevention. When the study ended and the men no longer received the shots,
about 95 percent of men said their sperm count returned to normal within a year. About five
men said after 18 months their sperm returned to normal and one man said his sperm count
never returned to normal even after four years. Over 75 percent of the men in the study said
they would be interested in using this type of contraception if it became available in the
future. However, some men had some side effects such as mood disorders, acne pain at the
site of the injection and increased libido.
The researchers said that about 60 percent of the side effects were due to the hormonal shots.
Most of the side effects were mild to moderate, but two men suffered depression that was
severe, so they stopped receiving the injections. The researchers said that changing the
timing of the shots could reduce the side effects of depression. The study was funded by the
United Nations/World Health Organization, and the non-profit organization CONRAD
(Contraception Research and Development), using funds from the Bill & Melinda Gates
Foundation and the U.S. Agency for International Development. The hormonal shots were
provided by the pharmaceutical company Schering AG, which has since merged with Bayer
Pharma AG.
Hashtags: #MaleContraception 
