397 URINARY GONADOTROPINS IN THE MANAGEMENT OF IDIOPATHIC PRECOCIOUS PUBERTY

The use of medroxyprogesterone acetate (MPA) in the treatment of idiopathic precocious puberty (IPP) is not standardized. In attempting to provide objective criteria for its use, we report the first patient in whom FSH and LH excretion rates have been measured in acid/acetone extracts of timed urine fractions sequentially before and after treatment. A 3 year old girl with IPP had enormously elevated gonadotropin excretion rates at presentation. She was treated with IM MPA 100 mg q3-4 weeks for 9 months, then p.o. MPA 5 mg q8h for 12 months. While on IM treatment, gonadotropin excretion rate fell dramatically and was associated with decreased breast size and height velocity. All these parameters increased when oral therapy was used. There have been no signs of glucocorticoid effects, hypertension, nausea, or excess weight gain. Bone age was 6 yrs 10 mos at presentation; 2 yrs later it was 8 yrs 10 mos. Although similar studies will be required in a larger number of patients, from these data we conclude that (1) sequential measurement of urinary FSH and LH excretion rates may optimize the MPA management of patients with IPP by providing objective criteria for monitoring therapeutic response (2) oral treatment,in the dosage used, is less effective than IM treatment.