The hormonal injection (also known as “Depo-Provera”) contains the hormone progestin, which works in a few different ways to prevent pregnancy. It prevents ovulation (the release of an egg from an ovary), and since no egg is released, the sperm has nothing to fertilize and pregnancy can’t happen. Progestin can also thicken the mucus around the cervix(entrance to the uterus), which makes it hard for the sperm to move. Finally, progestin can thin the lining of the uterus, making it hard for the egg to attach to the wall of the uterus.

How effective is it against pregnancy?

• Typical use: Prevents pregnancy 96% of the time
• Perfect use: Prevents pregnancy 99% of the time
• Using the shot correctly and consistently increases its effectiveness. If you use the shot perfectly, it is about 99% effective at preventing pregnancy.

How to Use:

• Get a shot every 3 months

Pros:

• Usually decreases periods
• Easy to use, low effort (“get it and forget it”)
• Can be used while breastfeeding

Cons:

• May cause spotting
• May cause weight gain, depression, hair or skin changes, changes in sex drive
• Side effects may last up to 6 months after stopping the shots
• Does not protect against HIV or other STIs – use a condom with this method