Journal of Clinical Endocrinology & Metabolism, Vol 64, 513-518, Copyright © 1987 by Endocrine Society

ARTICLES

Free estradiol, free testosterone, and sex hormone-binding globulin in perimenopausal women

C Longcope, SL Hui and CC Johnston Jr

To determine whether menstrual status had an effect on plasma sex hormone-binding globulin (SHBG) capacity and nonprotein-bound estradiol (% free E2) and testosterone (% free T), we measured these as well as plasma FSH, total E2, and T and the MCRs of E2 and T in a group of 78 perimenopausal women. The women were allocated to 4 groups: women with cycles whose plasma FSH level was less than 40 mIU/mL (A; n = 16), women with cycles whose plasma FSH level was greater than 40 mIU/mL (B; n = 19), women who were amenorrheic for less than 1 yr (C; n = 13), and women who were amenorrheic for more than 1 yr (D; n = 30). The mean plasma SHBG values were 51.4 +/- 5.7 (+/- SE), 48.3 +/- 4.3, 45.9 +/- 5.4, and 51.1 +/- 3.7 nM in groups 1-4 respectively, and were not significantly different from one another. The mean % free E2 and % free T values also were not different between the groups. However, the mean total E2 and free E2 (% free E2 X E2/100) concentrations were significantly (P less than 0.05) higher in both groups A and B than in groups C and D. The E2 concentration was also higher in group A than in group B. There were strong correlations between the E2 and free E2 concentrations between the T and free T (% free T X T/100); (P less than 0.0001) concentrations, between SHBG capacity and weight, and between the MCRs of both E2 and T and % free E2 and % free T. In normal women, the menopause is not associated with changes in SHBG or % free steroids. Hence, the measurement of E2 could be used to predict the mass of free E2 in these women.

This article has been cited by other articles:

				R. M. Lovering and W. A. Romani Effect of testosterone on the female anterior cruciate ligament Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2005; 289(1): R15 - R22. [Abstract] [Full Text] [PDF]

				Endogenous Hormones and Breast Cancer Collaborativ Free Estradiol and Breast Cancer Risk in Postmenopausal Women: Comparison of Measured and Calculated Values Cancer Epidemiol. Biomarkers Prev., December 1, 2003; 12(12): 1457 - 1461. [Abstract] [Full Text] [PDF]

				S. Rinaldi, A. Geay, H. Dechaud, C. Biessy, A. Zeleniuch-Jacquotte, A. Akhmedkhanov, R. E. Shore, E. Riboli, P. Toniolo, and R. Kaaks Validity of Free Testosterone and Free Estradiol Determinations in Serum Samples from Postmenopausal Women by Theoretical Calculations Cancer Epidemiol. Biomarkers Prev., October 1, 2002; 11(10): 1065 - 1071. [Abstract] [Full Text] [PDF]

				S. L. Hui, A. J. Perkins, L. Zhou, C. Longcope, M. J. Econs, M. Peacock, C. McClintock, and C. C. Johnston Jr. Bone Loss at the Femoral Neck in Premenopausal White Women: Effects of Weight Change and Sex-Hormone Levels J. Clin. Endocrinol. Metab., April 1, 2002; 87(4): 1539 - 1543. [Abstract] [Full Text] [PDF]

				H. A. Feldman, C. Longcope, C. A. Derby, C. B. Johannes, A. B. Araujo, A. D. Coviello, W. J. Bremner, and J. B. McKinlay Age Trends in the Level of Serum Testosterone and Other Hormones in Middle-Aged Men: Longitudinal Results from the Massachusetts Male Aging Study J. Clin. Endocrinol. Metab., February 1, 2002; 87(2): 589 - 598. [Abstract] [Full Text] [PDF]

				C. Bukowski, M. A. Grigg, and C. Longcope Sex Hormone-binding Globulin Concentration: Differences Among Commercially Available Methods Clin. Chem., September 1, 2000; 46(9): 1415 - 1416. [Full Text] [PDF]

				C. Longcope, H. A. Feldman, J. B. McKinlay, and A. B. Araujo Diet and Sex Hormone-Binding Globulin J. Clin. Endocrinol. Metab., January 1, 2000; 85(1): 293 - 296. [Abstract] [Full Text]

				F. Labrie, A. Belanger, L. Cusan, J.-L. Gomez, and B. Candas Marked Decline in Serum Concentrations of Adrenal C19 Sex Steroid Precursors and Conjugated Androgen Metabolites During Aging J. Clin. Endocrinol. Metab., August 1, 1997; 82(8): 2396 - 2402. [Abstract] [Full Text] [PDF]