One hundred fifteen women under age 40 presenting with hypergonadotropic amenorrhea (follicle-stimulating hormone greater than 40 mIU/mL) were evaluated. Incomplete pubertal maturation and chromosomal abnormalities were more likely in the 18 women (15.7%) with primary amenorrhea than in those with secondary amenorrhea. The 97 women with secondary hypergonadotropic amenorrhea were significantly more apt to complain of symptoms of estrogen deficiency, have been pregnant before diagnosis, and have evidence of ovulation after diagnosis. Withdrawal bleeding occurred commonly (greater than 48%) in those women administered exogenous progestin. Immune abnormalities occurred with approximately equal frequency (17.4%), and spinal bone density was decreased in both groups.