Depo-Provera is the brand name of the birth control shot. This is an injectable form of the drug depot medroxyprogesterone acetate, or DMPA for short. DMPA is a man-made version of the hormone progestin.
DMPA was approved by the Food and Drug Administration in 1992. It is highly effective at preventing pregnancy. It is also very convenient — one shot lasts for three months.
How it works
DMPA blocks ovulation, the release of an egg from the ovaries. Without ovulation, pregnancy can’t occur. DMPA also thickens the cervical mucus to block sperm.
Each shot lasts for 13 weeks. After that, you must get a new shot to continue preventing pregnancy. It is important that you schedule your appointment to get the shot well before your last shot is due to expire. If you don’t receive the next shot in time, you risk becoming pregnant because of decreased levels of the drug in your body. If you can’t get your next shot on time, you should use a backup method of birth control.
The shot is generally not recommended for long-term use (longer than two years) unless no other method of birth control can be used.
Your doctor needs to confirm that it is safe for you to receive the shot. You can make an appointment to receive it right away after your doctor’s confirmation as long as you are reasonably sure you are not pregnant. Your doctor will usually give the shot in your upper arm or buttocks, whichever you prefer.
If you get the shot within five days of starting your period or within five days of giving birth, you are protected immediately. Otherwise, you need to use a backup contraception method for the first week.
You will need to return to your doctor’s office every 12 weeks for another injection. If 14 weeks or more have passed since your last shot, your doctor may require that you get a pregnancy test before giving you another shot.
The Depo-Provera shot is a highly effective birth control method. Women who use it correctly have a risk of pregnancy that’s less than 1 percent. However, this percentage increases when a woman doesn’t receive the shot at the recommended times.
Most women taking the shot have progressively lighter periods. Your period may even end up stopping entirely after you have received the shot for a year or longer. This is perfectly safe. Other women may get longer, heavier periods.
Other common side effects include:
- abdominal pain
- decrease in sex drive
Less common side effects of the shot include:
- weight gain (more common the longer you use it)
- hot flushes
- achy joints
- sore breasts
- hair loss
Women who use Depo-Provera may also experience decreased bone density. This happens more the longer you use it and stops when you stop using the shot. You will recover some bone mineral density after you stop using the shot, but you may not have full recovery. Your doctor may recommend you take calcium supplements and eat foods rich in calcium and vitamin D to help protect your bones.
Serious side effects
Though rare, serious side effects can occur. You should seek immediate medical attention if you start having the following symptoms while you’re on the birth control shot:
- major depression
- pus or pain near the injection site
- unusual or prolonged vaginal bleeding
- yellowing of your skin or the whites of your eyes
- breast lumps
- migraines with aura (a bright, flashing sensation that precedes migraine pain)
Pros and cons
The primary benefit of the birth control shot is its simplicity. However, there are also some drawbacks to this method.
If you are considering options for birth control, talk with your doctor. They can help you balance the facts about each option with your health history and lifestyle considerations to help determine which method of birth control is best for you.