Endocrine Abstracts

Obese boys tend to begin puberty later than their peers who are not overweight. This was a clinical observation made in the Clinic's population of overweight boys. The study described here follows from this observation. The study group consisted of 45 boys in the age 12-15 years with a BMI of 25 or over and were in SMR1. The control group consisted of age matched 15 boys with a BMI ranging from 12-15 and their maturity varied from SMR 2-4. These boys were attending the Clinic for unrelated purposes, usually elective surgery. After a full anthropometric study, blood was obtained between 0800 and 0900 hrs in the fasting state and tested for T4, TSH, PRL, LH, FSH, testosterone and oestradiol. Informed consent was taken from all participants and the protocol was approved by the Clinic's Ethical Committee. Three of the study boys were excluded as they had elevated TSH. Serum testosterone in the study and control boys was 0.97 vs. 3.36 nmol (0.28 ng/ml vs. 0.97 ng/ml), p=0.01. Oestradiol values in the study and control boys was 1.02 vs. 0.62 nmol/l (28 pg/ml vs. 18pg/ml), p<0.01. When the BMI of all the boys were plotted against their oestradiol levels, there was a significant correlation (r = 0.82, p=0.04) Our data show that there is considerable delay of puberty in obese boys, probably due to elevated oestradiol levels. The source of the oestradiol is unlikely to be aromatisation of androgen, but probably due to oestrogens produced in adipose tissue.