By 2030, an estimated 47 million women will be undergoing menopause each year. With the progressive increase in life expectancy, the number of women older than 50, and consequently in menopause, is much higher today than in previous decades. In the United States, the average life expectancy for women is about eighty years, indicating not only a greater number of postmenopausal women but also that these women will live more than one third of their lives deprived of estrogen. The authors investigate the levels of the two important hormones, FSH and E2 during perimenopause. Levels of thyrotropin...