 Eligible women will be invited by their primary care physician to participate in the study. After signing an informed consent women will be randomized to receive oral vitamin D 100,000 IU or similar placebo once a month for three consecutive months. Pertinent clinical and demographic date will be documented and relevant laboratory test will be performed by the primary care team. One month after the third dose the same data and tests will be retrieved on each woman. Compliance with the study protocol will be enhanced and confirmed by a research assistant. 