I see it in my clinic all the time. A young woman sits across from me, juggling school, a new job, a busy life. “Doctor,” she’ll say, “I just can’t remember to take a pill every single day. Is there something… easier?” For many, the idea of a simple, long-acting contraceptive is a huge relief. One of the options we often discuss is the birth control shot, most commonly known by its brand name, Depo-Provera®. It’s a choice that offers freedom from daily reminders, but like any medical decision, it comes with its own set of things to consider.
So, let’s talk about it, just you and me.
What Exactly is the Birth Control Shot?
The birth control shot is an injection that contains the hormone progestin (a synthetic version of progesterone). In the clinic, we typically inject it into the muscle of your arm or buttocks. It’s a “set it and forget it” method for about three months.
Here’s how it works its magic:
- It stops ovulation. The progestin signals your body to not release an egg from the ovary. No egg means no chance for pregnancy. Simple as that.
- It thickens cervical mucus. This makes it much harder for sperm to swim through the cervix and reach an egg, if one were to be released.
When used perfectly—meaning you get your shot right on time, every time—it’s over 99% effective. But life happens! We forget appointments. In the real world, its effectiveness is closer to 96%. This means that for every 100 people using the shot, about four may become pregnant in a year.
Getting Started: The How, When, and Where
Getting the birth control shot is straightforward. It’s a prescription, so we’ll have a chat first to make sure it’s a good fit for you.
You can start the shot at any point in your cycle, as long as we’re sure you’re not pregnant (we might do a quick test). If you get your first shot within the first five days of your period starting, you’re protected from pregnancy right away. If you start it at any other time, we recommend using a backup method, like condoms, for the first week.
You’ll need to come back for another shot every 12 to 14 weeks. Sticking to this schedule is really the only “job” you have with this method. There’s also a lower-dose version, Depo-subQ Provera 104, that you can be taught to inject yourself at home. It goes just under the skin instead of deep into the muscle.
Weighing the Pros and Cons
Every choice has its upsides and downsides. Let’s lay them out honestly.
| The Advantages (The “Pros”) | The Disadvantages (The “Cons”) |
|---|---|
| Highly effective and private. No one needs to know, and you don’t need to do anything before sex. | Requires clinic visits. You have to schedule and show up for an appointment every 3 months. |
| Fewer or no periods. Many people love that their periods become lighter or stop altogether after a year. | Side effects are possible. We’ll talk more about these below. If you have them, you can’t just “stop” the shot; you have to wait for it to wear off. |
| No daily pill to remember. This is a huge plus for many busy people. | Delayed return to fertility. It can take, on average, about 10 months after your last shot to conceive. |
| Doesn’t contain estrogen. This makes it an option for some people who can’t take estrogen-based birth control. | No protection from STIs. You still need condoms to protect against sexually transmitted infections. |
Let’s Talk About Side Effects and Risks
Your body’s reaction to any hormone is unique. The most common side effect by far is a change in your period. It might be irregular spotting at first, and then after a year, more than half of users stop having a period at all. This is perfectly safe.
Other possible side effects include:
- Weight gain (Some studies show an average of about 5 pounds after a year, but not everyone experiences this.)
- Headaches
- Bloating
- Nervousness or mood changes
- Dizziness
The most important risk to discuss is its effect on bone density. The shot can cause a temporary loss of bone mineral density.
Because of this, we generally recommend using Depo-Provera for about two years at a time. If you wish to continue longer, we might suggest a break or do a bone density test to make sure your bones are staying strong. The good news is that this bone loss is generally reversible after you stop the shot.
Is the Shot a Good Fit for Everyone?
Depo-Provera is safe for most, but it’s not the best choice for everyone. We’ll need to talk about other options if you have a history of:
- Breast cancer
- Serious liver disease
- Unexplained vaginal bleeding
- Certain risk factors for stroke or heart disease
- Lupus with specific antibodies
If you are breastfeeding, we usually advise waiting until your baby is at least 6 weeks old before starting the shot, as a small amount can pass into your breast milk.
Take-Home Message
- The birth control shot (Depo-Provera) is an injection of the hormone progestin that prevents pregnancy for about 3 months.
- It works by stopping ovulation and thickening cervical mucus. With typical use, it’s about 96% effective.
- Changes in your period are the most common side effect. Many people stop having periods altogether after a year, which is safe.
- A key risk is temporary bone density loss, so use is often limited to around two years. We’ll monitor this with you.
- It can take an average of 10 months for fertility to return after your last shot.
- It does not protect against STIs, so using condoms is still important for your sexual health.
Choosing a birth control method is a deeply personal decision. There’s no single “best” option—only what’s best for you, your body, and your life right now. Let’s figure it out together.