Conclusion: The reference ranges for serum markers of bone turnover including OC, P1NP, and beta-CTX were 15.57 ± 4.75 ng / mL, 41.98 ± 16.62 μg / L, and 314.03 ± 150.42 pg / mL, respectively, in premenopausal women aged 20 to 44 years.