Effects of an oral contraceptive (norgestimate/ethinyl estradiol) on bone mineral density in women with hypothalamic amenorrhea and osteopenia: an open-label extension of a double-blind, placebo-controlled study

Objective: The effects of long-term triphasic oral contraceptive administration on bone mineral density (BMD) were investigated in premenopausal women with hypothalamic amenorrhea (HA) and osteopenia. Methods: After completing three 28-day cycles in the double-blind phase of a placebo-controlled trial, women (mean age, 26.7 years) who received norgestimate 180-250 mu g/ethinyl estradiol 35 mu g (NGM/EE, n = 15) or placebo (n = 12) in the double-blind phase were to receive open-label NGM/EE for 10 additional cycles. Results: For subjects completing 10 NGM/EE treatment cycles, mean posteroanterior total lumbar spine BNID (L1-L4) increased from 0.881 +/- 0.0624 g/cm(2) at baseline (last visit prior to NGM/EE) to 0.894 +/- 0.0654 g/cm(2) at final visit (p=.043); no significant changes in hip BNID occurred. Decreases in N-telopeptide, osteocalcin, procollagen type I propeptide and bone-specific alkaline phosphatase levels indicated effects on bone metabolism. Conclusions: Long-term administration of triphasic NGM/EE to osteopenic women with HA may increase total lumbar spine BMD. (c) 2005 Elsevier Inc. All rights reserved.