The Shot (Depo-Provera™)
What is it?
Depo-Provera™ is a hormonal birth control method that contains the hormone progestin. It is administered by injection and is 99.7% effective in preventing pregnancy. A prescription is required and your health care provider will administer the injections.
How does it work?
Depo-Provera™ :
- Stops the ovaries from releasing an egg,
- thickens the mucous of the cervix, and
- thins the lining of the uterus.
Your very first injection is usually given during the first five days of your period in your arm or buttocks, although it may be given at any time in the cycle if there is no chance you are pregnant. It becomes fully effective 24 hours after the injection. Injections are given every 12 weeks by a healthcare provider. Injections can be given as early as 10 weeks or as late as 14 weeks if needed.
Why use Depo-Provera™?
- Injection only administered four times a year.
- It is a highly effective form of birth control, particularly for women who cannot take estrogen.
- Women experience fewer or no periods, and less menstrual cramping and pain.
- Can be safely used by breastfeeding mothers.
- Can be used by women over the age of 35 who smoke.
What if the injection is two or more weeks late?
You are no longer protected by Depo-Provera™ and will need to use a back-up method of birth control (i.e., condoms) until you can visit your health care provider.
Possible Side Effects:
- Irregular bleeding is common in the first few months, although some women have no bleeding at all. After one year of use, up to 55% of women stop having periods.
- Headache (most common), mood changes, acne, decreased sex drive, nausea and breast tenderness.
- Weight gain may occur for some women (the average weight gain in the first year is about five pounds and may be due to increased appetite and food intake).
Possible Risks:
- Decreased bone mineral density (bone density improves when injections are stopped but may take up to two years to return to normal levels). This is particularly important for adolescents, who are in the process of reaching peak bone mass. Women should make sure they maintain bone health by getting enough Calcium and Vitamin D, either from their diet or from vitamin supplements, by doing weight training exercises, decreasing their intake of caffeine and alcohol, and quitting smoking.
- Return of fertility may be delayed for an average of nine months after stopping the injections.
What else should I know?
Do not take Depo-Provera™ if:
- You have a history of liver disease or breast cancer,
- you currently have cardiovascular disease, or
- you are less than 6 weeks postpartum and breastfeeding.
If you have any questions, call KFL&A Public Health Sexual Health.
Remember that Depo-Provera™ does not protect you from sexually transmitted infections (STIs). If you have made an error in using Depo-Provera™ and have not used back-up birth control, ask your healthcare provider, pharmacist, or KFL&A Public Health about emergency contraception (Plan B). Condoms are the best way to protect against STIs.
Revised: 2016-01-18