Menstrual irregularity in athletes: basic principles, evaluation, and treatment.

Recent advances in reproductive physiology have led to an understanding that the ovarian follicle controls the entire menstrual cycle. The most mature follicle, which is the best estrogen-producer, is most sensitive to gonadotropin stimulation and is destined to ovulate next. During the course of a training program, an athlete may be subjected to many factors including loss of weight and fat, low weight and fat, acute and chronic hormonal changes, and physical and emotional stresses. Each of these, alone or in combination, may be associated with menstrual irregularity or amenorrhea. Although menstrual irregularity and amenorrhea are common among athletes, these problems should always be evaluated thoroughly. It is dangerous to assume that such problems are either exercise-related or not serious. Athletes are not immune from developing significant pathology, which can be detected only if sought. Therapy is indicated for some women who have such menstrual dysfunction.