The female reproductive cycle: new variations on an old theme.

Understanding the female reproductive cycle is the essence of the practice of reproductive medicine. This article reviews important publications that shine new light on the female reproductive cycle. Menstrual dysfunction can begin at adolescence and persist throughout the reproductive years. Adolescent women with menstrual dysfunction should be evaluated and treated. Approximately 30% of pregnancies terminate in abortion during the first trimester. New epidemiologic data on the etiology of spontaneous abortion are reviewed. Advancing age is associated with a decline in fecundity. Delay in childbearing and advances in assisted reproductive technologies have enabled reproductive endocrinologists to better understand the effects of advancing age on reproductive function. The most important paper that we received supports the timing of breast cancer to the luteal phase of the menstrual cycle. There was a statistically significant increase in 10-year survival in women who had surgery during the luteal phase compared with the follicular phase.