Quite possibly. Two major studies have shown a higher fracture rate among premenopausal women (your age group) who used birth control pills. Other research suggests that this is even true when women using the pill also did high impact exercises. The effects of the pill seem to lessen the bone-building effects of exercise.

Surprisingly, one study showed that women who used the pill and didn't exercise had better density in their spine bones than those using the pill who exercised regularly. This highlights the negative effect of exercise on bone health among women who use oral contraceptives. If you're concerned about the health of your bones, make a point of talking with your health care provider about things you can do to optimize your bone health.