How effective are contraceptive injectables?
Progestin-only injectable contraception is highly effective when used correctly, with a typical success rate of less than 1 pregnancy per 100 women each year.
What are the side effects of progestin-only injectable contraception?
Possible side effects can include irregular menstrual bleeding, weight gain, headaches, and mood changes. In some cases, decreased bone density is a side effect, but this is reversible after stopping the injections. Fertility usually returns sometime after the last injection, but this can vary among individuals.