The bone density and osteoporosis side effects of Depo-Provera come from studies released in 2004, which also indicated that such bone loss may not be reversed once the woman stops using the injection.
As a result of these potential side effects, long-term use of the injection is not advised, and women taking Depo should exercise and consume an appropriate amount of calcium.
Additionally, according to the health center, if a woman becomes pregnant while taking Depo-Provera injections and continues with the pregnancy, there could be a potential increased risk of delivering a premature baby. After the last injection is taken, it could take more than six months for the drug to fully leave the body, and side effects may continue until this occurs, the health center says.
According to the American Pregnancy Association, other less serious side effects of taking Depo-Provera include headache, fatigue and nausea.