Pasco J A, Kotowicz M A, Henry M J, Panahi S, Seeman E, Nicholson G C
Department of Medicine, St Vincent's and The Geelong Hospitals, the University of Melbourne, Geelong, Victoria, Australia.
Am J Obstet Gynecol. 2000 Feb;182(2):265-9. doi: 10.1016/s0002-9378(00)70209-2.
We sought to test the hypothesis that exposure to oral contraceptives protects the skeleton.
Multiple regression techniques were used to analyze data for a random sample of 710 Australian women (age range, 20-69 years). Bone mineral density was measured at the lumbar spine, proximal femur, whole body, and distal forearm. Oral contraceptive exposure was assessed by a questionnaire.
Women exposed to oral contraceptives had a 3.3% greater mean bone mineral density adjusted for body mass index and age at the lumbar spine (partial r (2) = 0.009; P =.014). Adjusted mean vertebral bone mineral density was 3.3% greater for premenopausal women (partial r (2) = 0.008; P <.05), but the effect did not reach significance among postmenopausal women. Higher bone mineral density was associated with increased duration of exposure, with a mean increase of 3.2% associated with the first 5 years and a further 0.2% with >/=5 years of exposure. No association was detected at other sites.
Exposure to oral contraceptives may be associated with higher lumbar spine bone mineral density.
