The ins and outs of the birth control shot: Depo-Provera side effects, effectiveness, and cost

last updated: Dec 09, 2021

7 min read

Does the idea of only having to think about birth control every three months appeal to you? What if you could do it yourself, at home? (Are you intrigued yet?) Well, here are the need-to-knows about the contraceptive shot.

Read on to find out about:

  • What the birth control shot is and how it works

  • The different types of birth control shots

  • The pros and cons of the shot

  • Who shouldn’t use the shot

  • What’s it like to get and use the shot

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What is the birth control shot?

The contraceptive shot is an injectable method of birth control that protects you from pregnancy for three months. You can get the injection from your healthcare provider, and in some cases, you can even administer it yourself. (Score!)

There are two types of Depo shots:

  • The original Depo shot (aka DMPA): The brand name for Depo-Provera medroxyprogesterone acetate, a progestin — the main ingredient in the contraceptive shot. The shot is injected deep into the muscle and must be administered by a healthcare provider.

  • Depo-Provera-SubQ Provera 104: A lower dosage of medroxyprogesterone acetate, which is injected just beneath the skin. You can give yourself this shot at home — more on this later.

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The original Depo-Provera

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The Depo-Provera-SubQ Provera 104

We'll be concentrating on Depo-Provera and Depo-Provera-SubQ Provera in this piece, but there's another kind of injectable birth control: combination birth control shots (Cyclofem and Mesigyna), which are a lot like birth control pills in that they contain a combination of estrogen and progestin. They must be administered every 28 to 30 days. Currently, though, combination birth control shots aren’t available in the US.

How does the birth control shot work?

Like other birth control methods containing the hormone progestin, Depo-Provera prevents pregnancy by:

  • Suppressing ovulation (release of an egg about halfway through the menstrual cycle)

  • Thickening your cervical mucus to keep sperm from reaching an egg

How effective is the birth control shot?

Depo-Provera is 94% effective at preventing pregnancy when it's administered correctly. It works immediately if you get the shot during your period — no need for backup birth control. If not given during your period, you'll need to use backup birth control for a week after the injection. You need a new injection every 12-13 weeks (four times a year) in order for it to be effective.

The upsides, the downsides, and the good-to-knows

Before you go all in for the birth control shot, it’s important to consider all of the pros and cons. Your doctor will walk you through everything at your visit, but in case you want some of that knowledge ahead of time, keep reading. Below, we cover the benefits, risks, and other useful info to make the best decision for you.

What are the benefits of the birth control shot?

According to the Centers for Disease Control, Depo-Provera is the fourth most popular form of birth control in the US (25% of women have used it at some point).

Why is it so popular? For Sophia, who used Depo-Provera for years, it was the freedom that came with it: "I liked the fact that I was free to go about my life without having to remember to take a pill daily or insert a ring weekly. I also found benefit in having little to no menstrual cycle."  

But that’s not all that’s great about the birth control shot:

  • There’s no estrogen involved (unless you're using the combination shots), so it’s a good choice if you're trying to avoid estrogen for any reason.

  • It can actually treat symptoms of endometriosis by preventing ovulation and decrease the risk of endometrial cancer by protecting the endometrial lining.

  • You don't have to interrupt sex to use it.

  • It reduces menstrual cramps and pain.

  • In one study, amenorrhea (the absence of your period) occurred in 55% of women after the first year of using Depo-Provera, and in 68% of women by month 24.

What are the side effects of the birth control shot?

Depo-Provera and Depo-Provera-SubQ Provera 104 have similar risks. Both decrease the production of estrogen and can cause the cessation of your period while you're on it (also called amenorrhea). Decreased estrogen is linked to a loss in bone mineral density, which can lead to a decrease in bone mass and bone density, resulting in the development of osteoporosis and bone fractures later in life.  

Because of this concern, in 2004, the Food and Drug Administration (FDA) added warnings to Depo-Provera packages that the birth control shouldn't be used for longer than two years. However, in June 2014, the American College of Obstetricians and Gynecologists (ACOG) concluded that while healthcare providers should notify patients about this warning and discuss it with them, it shouldn't stop them from prescribing Depo-Provera or encouraging its use beyond two years. Longitudinal studies also demonstrate that any bone mineral density loss that occurs is largely reversible.

The following common side effects should decrease/stop within the first few months of use of Depo-Provera:

  • Abdominal pain

  • Bloating

  • Decreased interest in sex

  • Depression

  • Dizziness

  • Headaches

  • Irregular menstrual periods and bleeding

  • Nervousness

  • Weakness and fatigue

  • Weight gain (25% of users gained weight in the first six months)

Hair loss can also happen to some women while taking Depo-Provera. In one study, 10% of adolescents on Depo-Provera discontinued use because of hair loss — and the side effect was also reported in a clinical study of 3,900 women who used Depo-Provera for up to seven years.

If you’re taking Depo-Provera, these serious side effects can indicate the need for urgent medical care:

  • Depression that lasts longer than a few months

  • Heavy bleeding or concerns about your bleeding patterns

  • Trouble breathing

  • Pus, prolonged pain, redness, itching, or bleeding at the injection site

  • Severe lower abdominal pain

  • A serious allergic reaction

  • Any other symptoms that concern you

Are there any other downsides to the birth control shot?

This is more of a good-to-know than a downside: Depo-Provera protects against pregnancy — but not in the slightest against sexually transmitted infections (STIs). Only barrier methods of contraception, like condoms, do. If you and your partner haven’t been tested for all of the things, keep the condoms handy.

How can the birth control shot impact fertility?

Depo-Provera may not be right for you if you're looking to get pregnant soon after stopping birth control because there can be a delay in resuming ovulation. OB-GYN and Modern Fertility medical advisor Dr. Eva Luo, MD, MBA tells patients “as a rule of thumb” to expect that the birth control shot will likely interrupt periods for longer than other contraceptive methods.

Dr. Luo cites a study in which 50% of women who discontinued Depo-Provera conceived within 10 months. For a small percentage of women, however, pregnancy did not occur until 18 months after stopping the injections. The study also indicates that the delay in fertility has nothing to do with how long you've been on Depo-Provera, but is instead about body weight. Luo summarizes: "The heavier you are, the longer it can take."

How much does the birth control shot cost (and will insurance cover it)?

Without insurance, the birth control shot usually costs around $60 each, making it $240 a year (since you need a new one every three months). If you don't have insurance, Planned Parenthood offers programs to make the shot (and other birth control options) affordable. With insurance, however, the shot may be low cost or even free. Check with your insurance provider to find out what they cover. When planning financially for your shot, remember to also factor in the cost of doctor's visits.

Is there anyone who shouldn’t get the birth control shot?

Depo-Provera may not be an option for you if you have:

  • Unexplained vaginal bleeding

  • Breast cancer

  • Liver disease

  • Sensitivity to any component of Depo-Provera

  • Risk factors for osteoporosis

  • A history of depression

  • A history of heart attack or stroke

  • history of blood clots in your arms, legs, or lungs

What’s it like to get the birth control shot?

Before you're prescribed either type of Depo shot, your doctor will also review your medical history, and possibly take your blood pressure. You may also be given a pregnancy test. Once it's been confirmed that Depo-Provera is right for you, your doctor will talk to you about a start date based on your period (your injection will likely be given within seven days of your period beginning). Depending on when that date is, they may recommend that you use a backup method of birth control (like a condom) for a week after that first injection.

Talk to your doctor if you want to administer your own injections at home (more on this in a minute), but here's what you can expect if you elect to have your injection given in the office:

  • The injection site (either your upper arm or your butt) will be cleaned with alcohol.

  • Depo-Provera is injected… and that's it! (Just don’t massage the injection site.)

  • You’ll schedule your next shot (for 12-13 weeks later) while you're in the office so you don't forget.

Because Depo-ProveraSubQ is injected into the skin instead of the muscle, and it comes in a syringe that's already filled, you can actually give yourself the shot at home. You'll want to do this on the first day of your period, or up to five days later. If you do it at another time, you and your provider should confirm that you aren't pregnant — and you'll need to use another form of birth control for seven days after the shot.

Make sure you have the following available in advance:

  • A prescription (because SubQ is a newer option, it might take the pharmacy a few days to fill it — so plan ahead)

  • Alcohol pads

  • Prefilled syringe with SubQ Depo-Provera

  • safe place to dispose of your used needles

  • The instructions for administering the shot (which come with the medicine)

Giving yourself the shot:

  • Wash your hands with soap and water.

  • Take the syringe out of the package and shake it to make sure the medicine is well mixed.

  • Make sure there are no air bubbles in the syringe by holding the needle so that it's pointing up and tap it so that any air bubbles move to the top. Then push the syringe until the air bubbles are gone.

  • Decide where you want to inject yourself: belly or upper thigh?

  • Prep the injection site by wiping the skin with the alcohol pad and wait for it to dry.

  • Uncap the syringe and hold it in your dominant hand.

  • Now, grab the skin around the site where you're planning to inject yourself and insert the needle all the way into the skin at about a 45-degree angle. You might feel a twinge.

  • Count to five, keeping the needle in place.

  • Remove the needle and dispose of it.

  • Apply pressure to the injection site and then put a bandage on it (if you want).

  • You might see a little blood or have some redness or itching at the site, but that should go away in a few days.

  • You did it!

This article was medically reviewed by Dr. Eva Marie Luo, an OB-GYN at Beth Israel Deaconess Medical Center and a Health Policy and Management Fellow at Harvard Medical Faculty Physicians, the physicians organization affiliated with the Beth Israel-Lahey Health System.


If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.

How we reviewed this article

Every article on Health Guide goes through rigorous fact-checking by our team of medical reviewers. Our reviewers are trained medical professionals who ensure each article contains the most up-to-date information, and that medical details have been correctly interpreted by the writer.

Current version

December 09, 2021

Written by

Chanel Dubofsky

Fact checked by

Eva Marie Luo, MD, MBA, FACOG

About the medical reviewer