Injectable Contraception

Medically reviewed by Drugs.com. Last updated on May 6, 2024.

What is injectable contraception?

Injectable contraception is birth control medicine that is given as a shot. This medicine helps prevent pregnancy. The shot is usually given once every 3 months on day 1 to 5 of your menstrual cycle. The medicine may decrease blood loss and pain during your period. It also decreases your risk for anemia (low red blood cell count).

When can I start to use injectable contraception?

Tell your healthcare provider about any medical condition you have. Also tell him or her if you are currently breastfeeding. Your provider will tell you when you can start injectable contraception. You may need to use a different method of contraception for the first 7 days after you get the shot. You may need blood or urine tests before you start this medicine. You may use this method in any of the following situations:

During your menstrual cycle, you can start to use injectable contraception. You should get your first shot within 5 days after your cycle starts, if you have regular menstrual cycles. If you have irregular bleeding or no periods you may get the shot any time.
When you switch methods of contraception, you may need injectable contraception until your new method is working. This may decrease your risk of becoming pregnant.
After you give birth, your healthcare provider will tell you when to get the shot if you are breastfeeding. If you are not breastfeeding, you may have the shot any time.

What are the risks of injectable contraception?

Injectable contraception does not protect against sexually transmitted diseases. You may have headaches or changes in your mood. You may have heavy periods or periods that last longer than normal for you. Your periods may stop completely. You may have an upset stomach. You can develop brittle bones and be at higher risk for a fracture. You may gain weight. Certain medicines can prevent injectable contraception from working correctly.

How can I care for myself while I use injectable contraception?

Do not smoke. Nicotine and other chemicals in cigarettes and cigars increase your risk for a blood clot while you use injectable contraception. Ask your healthcare provider for information if you currently smoke and need help to quit. E-cigarettes or smokeless tobacco still contain nicotine. Talk to your healthcare provider before you use these products.
Increase your daily intake of calcium and vitamin D as directed. This will help make your bones stronger and prevent fractures. Foods rich in calcium include milk, yogurt, and cheese. You may need to take to take vitamins with calcium and vitamin D. You should get 1,300 mg of calcium and 400 IU of vitamin D per day when using injectable contraception. Talk to your healthcare provider before you take vitamins.
Exercise regularly. Weight-bearing exercise will help you build bone and muscle strength. Walking is an example of a weight-bearing exercise. Ask your healthcare provider about exercises that are right for you. Try to get at least 30 minutes of exercise on most days of the week. Your provider can tell you if you need to exercise more than this.

When should I contact my gynecologist or doctor?

You have heavy bleeding from your vagina.
You have yellow eyes or skin.
You have severe pain in your stomach or abdomen.
Your period lasts longer than is normal for you.
You do not get a period.
You have unprotected sex before you have your shots.
You have changes in your mood.
You have questions or concerns about injectable contraceptives.

Care Agreement

You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your healthcare providers to decide what care you want to receive. You always have the right to refuse treatment. The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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