Male Contraception Proven Effective in Chinese Study

China, the most populous country in the world, has announced that it is close to developing an effective male contraceptive injection after successfully carrying out the largest feasibility study to date.

Researchers from the Beijing-based Chinese National Research Institute for Family Planning reported last year a method for male contraception that is effective, reversible, and without serious short-term side effects.

In the test trial, conducted with nine other research centers around the country, 1,045 healthy fertile males were injected monthly with 500 milligrams of a formulation of testosterone undecanoate (TU) in tea seed oil during a course of 30 months. The androgen works by dramatically reducing two regulatory brain chemicals, follicle-stimulating hormone (FSH) and luteinising (LU), which in turn disrupt sperm production. 

About 6.1 percent of men did not react to the treatment, a failure rate similar to that of combined oral contraceptives, such as birth control pills. During the 24-month study period, only 1.1 men per 100 experienced contraceptive failure.

"For couples who cannot or prefer not to use only female-oriented contraception, options have been limited to vasectomy, condoms, and withdrawal," said Yi-Qun Gu, a professor with the Beijing-based National Research Institute for Family Planning's male clinic research department. "Our study shows a male hormonal contraceptive regimen may be a potential, novel, and workable alternative."

The tested men experienced mild side effects including weight gain and acne. After the hormone treatment, the participants' sperm count returned to normal levels. However, Gu cautioned that more extensive testing will be necessary to ensure long-term safety, particularly with regard to cardiovascular and prostate health, as well as concerns about how couples would adjust their contraceptive use.

The development may place male contraception on par with the female birth control pill, with an additional advantage that only monthly injections would be necessary. The introduction of the pill in 1960 revolutionized users' sex lives, but it placed the onus of reproductive responsibility on women. Male contraception may even out the responsibility - a development that many women would welcome as only fair if women learn to trust male contraception.

Male contraceptives may also offer an additional freedom of enjoying sex without the much more far-reaching consequences of reproduction for those who seek sex and do not necessarily want reproduction as the result.

The possibility of an additional means of contraception has arrived none too soon for China as the country continues to struggle with significant population growth. The United Nations estimates that the Chinese population increased from 1.266 billion in 2000 to 1.312 billion in 2005, and it is projected to grow from the present 1.315 billion to 1.396 billion by 2015. The average annual growth rate is declining, however, from 0.71 percent in the period 2000-05 to the current rate of 0.63 percent in the period 2005-10, and it is projected to decrease to 0.61 percent by 2015.

Population growth is occurring despite China's one-child policy. The at-large population has generally acquiesced to the policy, although the mandate has met with widespread criticism from human rights activists and others beyond China's borders. In urban areas, the policy is strictly enforced. In rural areas, where approximately 70 percent of Chinese live, enforcement is left to local officials and a second child is generally allowed, especially if the first child is a girl.

China's fertility rate - the number of children born per woman - was an estimated 1.75 in 2008, with the rate smaller in urban areas (1.3 children) than rural regions (2.0 children), according to the United Nations. Although there is now good evidence that China is becoming a small-family culture, especially as working couples opt for one-child families, the government faces a challenge as it strives to stabilize the population at 1.45 billion people by 2020.

Gioietta Kuo is a senior fellow with the American Center for International Policy Studies. She can be reached at kuopet@comcast.net.

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