Birth Control & Family Planning
Depo-Provera Birth Control Shot: Effectiveness, Side Effects and Fertility
The birth control shot (Depo-Provera, or just "Depo") is an injection of the progestin medroxyprogesterone acetate that you get every 3 months. With typical use, about 4 in 100 people get pregnant in a year, so it works better in real life than the pill, patch or ring. The trade-offs: irregular bleeding at first, possible weight gain, and a slower return to fertility after you stop.
What getting the shot is actually like
It's a quick visit. If you get the standard version, a nurse or clinician gives it in your upper arm or buttock muscle. It stings for a few seconds and your arm may be sore for a day, like after a flu shot. That's it until your next one in 3 months.
The self-injection version goes just under the skin of your belly or thigh with a small needle, and you can do it at home after someone shows you how. Many people who try it like skipping the clinic trip four times a year.
| Intramuscular (Depo-Provera CI) | Subcutaneous (depo-subQ provera 104) | |
|---|---|---|
| Where injected | Arm or buttock muscle | Just under the skin of the belly or thigh |
| Who gives it | A clinician | A clinician, or you at home |
| How often | Every 3 months | Every 3 months |
The CDC's 2024 practice recommendations say self-injection should be offered as an additional option. Ask whether your clinician and insurance support it.
How it works
The shot releases progestin slowly over about 3 months. It:
- Stops ovulation, so no egg is released
- Thickens cervical mucus, blocking sperm
There's no estrogen in it. That makes it an option for many people who can't use estrogen, including people who are breastfeeding or have migraine with aura.
How well does it work?
- Typical use: about 96% effective (about 4 pregnancies per 100 users per year)
- Perfect use: more than 99% effective
Most pregnancies on the shot happen because the next injection is late. CDC guidance allows the repeat shot up to 15 weeks after the last one without needing backup. The easiest fix: book your next shot before you leave the office, and put a reminder in your phone for two weeks before it's due.
The side effects people ask about most
"Why am I bleeding all the time?"
Irregular, unpredictable bleeding is the most common side effect, especially in the first few months. It's annoying, and it's the top reason people quit early. The good news is that over time many users get lighter periods or none. After about a year, a large share of users have stopped having periods altogether. That's not harmful, and plenty of people consider it the main perk.
"Will I gain weight?"
Some people do, and studies suggest it's more likely with the shot than with other hormonal methods. Not everyone gains weight. If this is a big concern for you, say so up front so your clinician can talk through alternatives.
Other side effects
- Headaches
- Breast tenderness
- Mood changes
- Lower sex drive
- Soreness where the shot went in
One honest downside: because each shot lasts 3 months, you can't stop a side effect right away the way you can by stopping a pill. You wait it out.
Myth vs. fact: the shot and your bones
Myth: The shot will give you osteoporosis.
Fact: The FDA label does carry a boxed warning that the shot can reduce bone mineral density, and that the loss may be greater the longer you use it. But:
- Bone density largely recovers after the shot is stopped, according to available research.
- ACOG advises that concern about bone loss shouldn't stop people from starting or continuing the shot, and routine bone scans aren't needed for most users.
- Calcium, vitamin D and weight-bearing exercise support bone health for everyone.
If you have other risk factors for osteoporosis, talk them over with your clinician.
Myth vs. fact: getting pregnant afterward
Myth: Depo makes you infertile.
Fact: It doesn't cause permanent infertility. But it's the one reversible method with a known delay in return to fertility. The hormone clears slowly, so it can take several months, sometimes a year or more after the last shot, for ovulation and regular cycles to return.
If you want to get pregnant in the next year or so, an IUD, implant or pill will get you back to baseline faster. Read more about coming off birth control.
Is the shot a good fit for you?
It may suit you if you:
- Want something private with no daily routine
- Can't use estrogen
- Are breastfeeding
- Would like fewer or no periods
- Don't plan to get pregnant soon
It may not be the best fit if you:
- Want to get pregnant within the next year
- Are very worried about weight gain
- Have certain conditions listed in the CDC Medical Eligibility Criteria, such as some types of heart disease, current breast cancer, or several strong risk factors for heart disease
How it compares to other progestin methods
| Shot | Implant | Hormonal IUD | Mini pill | |
|---|---|---|---|---|
| How often | Every 3 months | Up to 5 years | 3 to 8 years | Daily |
| Typical-use effectiveness | About 96% | More than 99% | More than 99% | About 93% |
| Fertility return | Can be delayed | Quick | Quick | Quick |
Compare every method in our birth control options guide.
Starting the shot
You can get your first shot any time you're reasonably sure you're not pregnant. Per CDC guidance:
- Within the first 7 days after your period starts: no backup needed.
- Any other time: use condoms or skip sex for 7 days.
The shot can also be given right after childbirth, after an abortion or miscarriage, or when switching from another method. Ask your clinician how to switch without a gap.
What if you're late?
If more than 15 weeks have passed, your clinician may still give the shot if they can reasonably rule out pregnancy, and will recommend backup for 7 days. If you had unprotected sex recently, ask about emergency contraception too.
Can you get it at a New York pharmacy?
Not yet. New York's 2024 pharmacist standing order covers the pill, patch and ring, but not the shot. You still need a clinician for the injection or a prescription for self-injection supplies. Bills to add injectables have been proposed, so ask your pharmacist about the current rules.
Does it protect against STIs?
No. The shot doesn't protect against sexually transmitted infections, including HIV. Use condoms if you or a partner could be at risk, and get tested regularly.
When to call your provider
Call your provider if you:
- Are more than 15 weeks past your last shot
- Have very heavy or long-lasting bleeding
- Notice depression or mood changes that worry you
- Have pain, pus or redness at the injection site that doesn't go away
- Have severe belly pain, or think you might be pregnant
- Have migraines that get worse
Your next step
OB/GYNs, women's health nurse practitioners and family planning clinics across New York give the shot and can teach self-injection. Search the directory to find one in your borough or county, and ask about self-injection when you book.
Frequently asked questions
How often do you get the birth control shot?
The shot is given every 3 months. CDC guidance allows a repeat shot up to 15 weeks after the last one without needing backup protection.
Can I give myself the Depo shot at home?
A subcutaneous version (injected just under the skin) can be self-administered at home. CDC's 2024 guidance recommends that clinicians offer self-injection as an option where available.
How long does it take to get pregnant after stopping Depo?
Fertility can take longer to return than with other methods. Many people conceive within about a year after their last shot, but for some it takes longer. It does not cause permanent infertility.
Does Depo-Provera cause bone loss?
The shot can lower bone mineral density while you use it, and the FDA label carries a warning. Bone density largely recovers after stopping. ACOG says the risk should not by itself stop most people from using or continuing the shot.
Sources
- FDA — Depo-Provera CI and depo-subQ provera 104 prescribing information
- CDC — U.S. Selected Practice Recommendations for Contraceptive Use, 2024
- CDC — U.S. Medical Eligibility Criteria for Contraceptive Use, 2024
- ACOG — Depot Medroxyprogesterone Acetate and Bone Effects (Committee Opinion 602)
- ACOG — Progestin-Only Hormonal Birth Control: Pill and Injection (patient FAQ)
This article is for general education and is not medical advice. It does not replace an evaluation by a licensed clinician who knows your history. If you think you have a medical emergency, call 911.