There is only one birth control shot on the market in the United States for women–the Depo-Provera. This shot is a progesterone-only hormonal contraceptive given once every three months. Outside the United States, a monthly contraceptive injection is available, marketed under the brand names Cyclofem or Lunelle. Birth control shots are effective, but they do have risks and side effects.
Depo-Provera is available from your physician, Planned Parenthood or local family planning clinics. This progesterone only shot is given in the arm and provides three months of reliable contraceptive protection with no risk of user error, forgotten pills or broken condoms. If you get your shots every 12 weeks, according to schedule, your risk of pregnancy is less than 1 percent. The actual use failure rate for Depo-Provera, sometimes called DMPA, is around 3 percent. The shot works by preventing ovulation, thickening cervical mucus and thinning the uterine lining. Common side effects include irregular bleeding, missed periods, nausea, weight gain, and depression. It can take from nine months to more than a year to become pregnant after stopping Depo-Provera. There is a risk of bone thinning with the progesterone-only birth control shot. This risk increases over time, but bone thinning is reversed once you stop using the shot.
Lunelle and Cyclofem are once-a-month injections that combine estrogen and progesterone, much like the common combination birth control pill. Neither of these birth control shots is available in the United States. Lunelle was on the market in the United States from 2000 to 2003 but was withdrawn after a recall, due to quality control issues. These shots have the same side effects and benefits as contraceptive pills. Lunelle may cause shorter, lighter periods and may help to regulate periods. While the combined hormones reduce side effects, nausea, breast tenderness and weight gain are possible. More serious risks include blood clots and stroke. Women who smoke should not use Lunelle.
The Male Shot
New research may lead to the development of a male birth control shot. A May 2009 study in “Journal of Clinical Endocrinology and Metabolism” authored by Yi-Qun Gu, M.D., of Beijing’s National Research Institute for Family Planning, has shown potential success with injections of testosterone undecanoate. Additional testosterone in the bloodstream tricks the body into stopping sperm production. It can take some amount of time for the hormones stop the production of sperm in the testes, approximately three months. While the public has a strong interest in a reliable male contraceptive like a birth control shot, pharmaceutical companies have less of one. This is a promising development, but one that is far from market-ready.