The menopausal transition Nanette Santoro, MD  The American Journal of Medicine  Volume 118, Issue 12, Pages 8-13 (December 2005) DOI: 10.1016/j.amjmed.2005.09.008 Copyright © 2005 Elsevier Inc. Terms and Conditions

Figure 1 A working model for ovarian aging across the menopausal transition. Ovarian reserve shrinks throughout life and reaches a critical threshold level at the inception of the menopause. At this point, a woman notes her first skipped menstrual period. The subsequent trajectory of loss of ovarian reserve can follow several time paths (indicated by the downward sloping lines), depending on modifying factors, such as a woman’s general state of health, her smoking status, and her genetic makeup. FMP = final menstrual period. The American Journal of Medicine 2005 118, 8-13DOI: (10.1016/j.amjmed.2005.09.008) Copyright © 2005 Elsevier Inc. Terms and Conditions

Figure 2 The inhibin hypothesis. As ovarian reserve declines throughout reproductive life, inhibin B (INH-B), a product of small growing follicles, decreases. Concomitant with this relative loss of INH-B, follicular phase follicle-stimulating hormone (FSH) increases in a reciprocal fashion. The American Journal of Medicine 2005 118, 8-13DOI: (10.1016/j.amjmed.2005.09.008) Copyright © 2005 Elsevier Inc. Terms and Conditions

Figure 3 Patterns of estradiol, progesterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) levels in a sample of 8 midreproductive-aged (MRA) and 14 older reproductive-aged (ORA) women. (To convert LH and FSH to international units per liter, multiply by 1; to convert estradiol to picomoles per liter, multiply by 3.67; to convert progesterone to nanomoles per liter, multiply by 3.18). Error bars indicate mean ± 1.0 SE. The American Journal of Medicine 2005 118, 8-13DOI: (10.1016/j.amjmed.2005.09.008) Copyright © 2005 Elsevier Inc. Terms and Conditions