Abstract
Objective: We sought to test the hypothesis that exposure to oral contraceptives protects the
skeleton. Study Design: 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. Results: 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 r2 = 0.009; P = .014). Adjusted mean vertebral bone mineral density was 3.3% greater for premenopausal
women (partial r2 = 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. Conclusion: Exposure to oral contraceptives may be associated with higher lumbar spine bone mineral
density. (Am J Obstet Gynecol 2000;182:265-9.)
Keywords
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Article info
Publication history
Accepted:
September 23,
1999
Received in revised form:
July 12,
1999
Received:
March 15,
1999
Footnotes
☆Supported by the Victorian Health Promotion Foundation and the Geelong Region Medical Research Foundation.
☆☆Reprint requests: Julie A. Pasco, PhD, The University of Melbourne, Department of Medicine, The Geelong Hospital, PO Box 281, Geelong 3220, Australia.
Identification
Copyright
© 2000 Mosby, Inc. Published by Elsevier Inc. All rights reserved.
