Clinical and endocrine studies on patients with amenorrhoea associated with weight loss.

Two hundred and forty-three patients with amenorrhoea associated with weight loss were studied. At the onset of amenorrhoea, regardless of percentage weight loss, basal levels of LH were low and LH responses to LHRH were impaired. However, both basal and stimulated levels of FSH were comparable to normal. With resumption of menstruation, the basal and stimulated levels of LH were found to rise to normal, while FSH responses continued to exceed normal. However, 16.6% of 66 unimproved cases had normal responses but remained amenorrhoeic. Furthermore, amenorrhoea persisted in 71% of 31 patients with complete recovery of body weight. No significant correlation was noted between percentage weight loss and responsiveness to LHRH, nor between recovery of body weight and resumption of menstruation. Return to normal weight is desirable for resumption of normal cyclic menstruation and hypothalamic-pituitary function, but is not always effective.