Depo-Provera injections are given every 3 months for contraception. This is the same synthetic progestin that is in PremPro. Depo-Provera has been a popular birth control option for women that have a hard time remembering to take a pill every morning. However, that convenience comes at a price. The Depo-Provera injections come with a black box warning that they cause bone loss in users. The longer women use the injections, the more bone density they lose…in some cases as much as 15% or more. There are 5 factors that seem to affect how much bone density a woman will lose while using Depo-Provera:

• Calcium intake-Having adequate calcium levels seems to slow the rate of bone loss. 
•  Vitamin D intake-Women with a low vitamin D level (which is very common in these days of sunblock and indoor living) are at much higher risk for bone loss.        
• Smoking-Smoking increases risk of bone loss dramatically.       
• Drinking alcohol- Women who drink tend to lose more bone density while using Depo-Provera
• Body Mass-Overweight women have been shown to lose the least amount of bone density.

After stopping the injections, a woman’s bones will start to rebuild. In the first 8 to 9 years after stopping injections, studies have shown a 15% increase in bone density on average. Some women won’t completely bounce back-usually the women with several of the risk factors listed above- but all of the women in the studies did show some improvement.

Researchers are now recommending monitoring serum vitamin D levels on all women using the Depo-Provera injections. Taking vitamin D supplements can help slow the expected bone loss.