Depo-Provera is an invisible form of birth control. The girl gets an injection with hormones, to be repeated every three months.
It works like oral contraceptives: preventing ovulation, changing the lining of the uterus and thickening the mucus at the cervix.
Shots are given in the buttocks or upper arm.
It’s a very reliable method. The expected failure rate is less than 1%.

The advantages and disadvantages