Objective
To determine whether estradiol (E₂), lipid profile, biochemical markers, and bone mineral density (BMD) are related according to postmenopausal period.

Method
One hundred fifty four women were divided into four groups according to the time past menopause: group I (0∼5 years), group II (6∼10 years), group III (11∼15 years), group IV (more than 16 years). Group I, II, III were subdivided into osteoporosis group (t-score＜⁣2.5) and non-osteoporosis group (t-score≥⁣2.5). E₂, lipid profile, osteocalcin, alkaline phosphatase, deoxypyridinoline, and BMD by DEXA were measured in all groups.

Results
There were significant inverse correlation between BMD and postmenopausal period (p＜0.05). Deoxypyridinoline and osteocalcin were correlated with postmenopausal period but there was no statistical significance. Deoxypyridinoline and osteocalcin were increased in osteoporosis group compared to non-osteoporosis group but there was no statistical significance. E₂ had significant inverse correlations with postmenopausal period (p＜0.05). E₂ had no correlation with factors such as biochemical markers and lipid profile in group I, II, III but had adverse correlation with deoxypyridinoline in group IV.

Conclusion
No specific biochemical markers regarding the duration of menopause were found. Regardless of the duration of menopause, checking both osteocalcin and deoxypyridinoline was statistically significant for the evaluation of postmenopausal osteoporosis.