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Depo Provera Shot

Depo Provera Shot

Depo-Provera Shot

Depo-Provera, a contraception drug, is a synthetic hormone (progestin), which is injected under the skin. It is 95-99% effective in preventing pregnancy for 3 months. For continued protection against pregnancy, women must return every 3 months for another injection. Each time a shot is given, a high level of progestin is released into the body. This unnaturally high level stops the natural production of both progesterone and estrogen. As a result, the ovary does not prepare an egg and the lining of the uterus is not prepared to support a fertilized egg. In addition, the cervix (opening to the uterus) secretes mucus that blocks sperm from entering the uterus

Understanding The Risks

  • You will have side effects from using this form of contraception. The most frequently reported side effects are weight gain, spotting, and irregular or heavy menstrual periods, decreased sex drive, depression, headache, nervousness, possible higher risk of breast cancer in women younger than 35, and anemia (low blood count).
  • This method DOES NOT protect against sexually transmitted infections (STIs), such as syphilis, gonorrhea, chlamydia, herpes, genital warts, hepatitis B or HIV. Only a barrier method of birth control like condoms, a diaphragm or cervical cap can provide protection from STI's.
  • Almost all women experience changes in their periods when using Depo-Provera such as: longer periods, spotting between periods (sometimes daily), or no periods at all.
  • The possible long-term effects are not yet known, but Depo-Provera has been associated with an increased risk of breast cancer in women under age 35.
  • You should not use Depo-Provera if you have: liver disease; breast cancer; blood clots, or unusual vaginal bleeding.
  • Do not use this drug if you are pregnant. The effects of Depo-Provera on the fetus are unknown, but there has been an association between Depo-Provera and birth defects.
  • Depo-Provera is secreted into breast milk--newborns that drink breast milk will definitely be exposed to the drug.
  • The FDA and Upjohn (the manufacturer of Depo-Provera) agree that women should not use Depo-Provera if they have ever experienced any of the following health problems: acute liver disease; breast cancer; blood clots in the legs, lungs or eyes; or any current unexplained vaginal bleeding.

Side Effects

There is no antidote that reverses the effects of Depo-Provera. You will have to wait before the effects of the drug eventually wear off as the levels of the drug slowly decline. Sometimes the unpleasant side effects last for several months after the last shot. Most women will not resume regular menstrual cycles right away. On the average, it takes ten months after the last shot before women are fertile again. Some women have not been able to get pregnant. Many women suffer from depression while taking Depo-Provera. Medical professionals may not recognize this strong connection and encourage women on Depo to also take anti-depressant drugs, instead of suggesting the woman stop taking Depo-Provera.

Studies of the risk of cancer in women using Depo-Provera have been conducted in other countries. The most disturbing results have been in the breast cancer studies. Three studies on Depo-Provera, found an increase in the risk of breast cancer in women less than 35 years old. These studies are not yet conclusive. Many scientists discount the increased risk for young women because they did not find an overall increased risk of breast cancer for all women exposed to Depo-Provera. We remain concerned about this possible risk. Long-term use of Depo-Provera may be the most likely to increase the risk of cancer, but very few long-term users were included in the studies.

Depo-Provera use may decrease the amount of calcium in your bones. The longer you are on Depo-Provera the more calcium you may lose. This increases the risk of your bones weakening if you use Depo-Provera continuously for a long time (for more than 2 years). The calcium may not return completely once you stop using Depo-Provera. The loss of calcium may increase your risk of osteoporosis and broken bones, particularly after your menopause. The decrease of calcium in your bones is of most concern if you are a teenager, young adult, or have the following risk factors:

  • bone disease
  • anorexia nervosa (an eating disorder)
  • a strong family history of osteoporosis
  • drug use that can lower the amount of calcium in bones (drugs for epilepsy or steroids), or
  • drinking a lot of alcohol or smoking a lot

Taking calcium and vitamin D may lessen the loss of calcium from your bones. It is recommended that you stop using Depo-Provera after 2 years. If you want to switch birth control, Women's Health Specialists can give you information about other methods.

There have been instances in this country and other countries where women have been pressured into using Depo-Provera or have been given the shot without understanding what it was. Only you as a woman can decide what the best method of birth control is for you.