The Pill And Your Bones

A new study finds that oral contraceptives may decrease the bone density of young women. Women who take The Pill for longer than two years as well as those taking low-dose estrogen pills seem to have the highest risk for developing decreased bone density. These effects are seen in both the spine and in the entire body, say the researchers.

Emerging Evidence

Delia Scholes, the study author for this trial commented, “I think the evidence is still emerging on this association, but our findings suggest that low-dose oral contraceptives with long-term use have some impact on bone density.” Scholes is with Seattle’s Group Health Cooperative where she is a senior investigator at the cooperative’s Group Health Research Institute. The findings of Schole’s work were published in Contraception’s January 2010 issue.

Scholes said that it’s still unclear just what the impact will be for the long-term on women under 30. Scientists still don’t know whether these reduced bone density findings can be reversed if a woman stops taking oral contraceptives. The researchers also do not know if this reduced bone density in younger women will be reflected by a greater risk for fractures as they age.

However, Scholes pointed out that, “if oral contraceptives are indeed causing the approximately 5 percent lower spine bone density for oral contraceptive users versus non-users that we observed in our study, and if that impact is not reversed with oral contraceptive discontinuation or with other factors that may occur across the life span, a 5 percent lower bone density after menopause is associated with approximately 50 percent more osteoporotic fractures.”

Important Implications

Right now, there are 12 million U.S. women using oral contraceptives. The use of this contraception method is highest in those women under the age of 30. This has important implications since the most significant amount of bone mass is produced while a woman is in her 20’s.

Earlier studies have shown different findings regarding a possible link between oral contraception and bone density. Some studies found there was no decrease in bone density and other studies showed there was an actual benefit in which bone mass was increased by the use of these contraceptives. Still other studies say that oral contraceptives may interfere with the ability to produce bone mass.

The current study involved 606 women between the ages of 14 to 30. The researchers looked at oral contraception use, how long women used them, the dose of estrogen in the pills, and the results of bone mineral density tests. These tests measured the bone density of the spine, hip, and entire body.