PLASMA CONCENTRATION OF OESTRADIOL-17β IN PREMATURE THELARCHE AND IN DIFFERENT TYPES OF SEXUAL PRECOCITY

Abstract

Plasma Oe₂ concentration was measured by radioimmunoassay in patients with premature thelarche, with precocious puberty and in 29 normal controls. The mean plasma Oe₂ was 1.5 pg/ml (0–7.2) in normal prepubertal girls, 23.8 ± 17.8 (sd) in pubertal girls, 50.2 (± 19.4) in the follicular phase, and 94.2 (± 19.5) in the luteal phase of normal adult females. Ten girls with premature thelarche had a mean of 7.7 ± 6.6 pg/ml. Three of them showed higher values than the other 7, suggesting that in these cases, elevated levels of plasma Oe₂ might have played a role in the development of breast tissue. Ten untreated girls with idiopathic precocious sexual development had a mean of 51.6 ± 42.9 pg/ml while 6 patients treated with 150 mg per week of medroxyprogesterone acetate had a mean of 11.4 ± 2.5 pg/ml. Two patients with Down's syndrome, hypothyroidism and sexual precocity had plasma Oe₂ of 144 and 31.5 which fell to 24.7 and 8 pg/ml, respectively, after thyroid replacement. One girl with a granulosa cell tumour had a basal value of 304 pg/ml and a concentration of 27 pg/ml after surgery.