Oral Contraceptive Use and Risk of Low Bone Density in Women Attending Menopause Clinics in Italy

Abstract

Osteoporosis is a major health care problem, which leads to a high incidence of spine, radial, and hip fractures. These are considered major causes of morbidity and mortality in the aging population. Bone mineral density (BMD) is an important determinant of fracture risk. It is now well recognized that a chronically hypoestrogenic state increases bone turnover that, in turn, causes a critical decrease in BMD [1 – 4]. This process is already present in perimenopausal oligomenorrheic women. Although hormone replacement therapy has been reported to prevent the reduction in bone density related to estrogen deficiency [5 – 6], these women cannot benefit from HRT and the sole supplementation of calcium at this phase is unable to arrest the loss in BMD. There are many studies in the literature reporting that the use of low-dose oral contraceptive (OC) administration may be an optimal preventive measure for perimenopausal decrease in radial [7] and vertebral [8] bone density. The observation of a protective effect of OC on the risk of hip fracture [9] is supported by the results of a longitudinal study, showing that, in perimenopausal oligomenorrheic women, the decrease in femoral bone density is reversed by the administration of a low-dose OC preparation [10]. In order to offer further data on this issue, we collected information in the framework of a large cross-sectional study on the characteristics of women around menopause attending a network of first level outpatient menopause clinics in Italy.