Anorexia nervosa is characterized by striking weight loss. Primary or secondary amenorrhea is frequently found in affected girls, and pubertal development is absent or minimal, depending on the level of weight loss. Regaining weight reverses the condition. Increased physical activity even without weight loss can lead to decreased menstrual frequency and gonadotropin deficiency. When physical activity is interrupted, menstrual function may return.
Hypothyroidism inhibits the onset of puberty and delays menstrual periods.
Infants and prepubertal boys are not identified owing to the absence of recognizable clinical features. Testosterone levels may be close to normal because Leydig cell function may be spared, but seminiferous tubular function is characteristically lost, causing infertility. The age of the onset of puberty is usually normal but secondary sexual changes may not progress because of inadequate Leydig cell function. Ovarian failure Patients with variants of Turner syndrome, gonadal dysgenesis, galactosemia, or following radiation therapy may have ovarian failure. Turner Syndrome Turner syndrome is a common cause of ovarian failure.