Diurnal rhythm of 17 beta-estradiol secretion throughout pubertal development in healthy girls: evaluation by a sensitive radioimmunoassay

J Clin Endocrinol Metab. 1996 Nov;81(11):4095-102. doi: 10.1210/jcem.81.11.8923866.

Abstract

Puberty is initiated by a nocturnal rise in gonadotropin secretion, which, in boys, results in an increased nocturnal secretion of testosterone. To characterize any similar diurnal rhythm of 17 beta-estradiol in healthy girls, we determined the secretion of 17 beta-estradiol before and during puberty. The study group consisted of 45 healthy girls whose height SD scores ranged from -3.7 to +4.9 compared with Swedish growth reference values. One to 6 profiles of 17 beta-estradiol (7 samples/24 h) were obtained from each girl during puberty and from 21 of the girls before clinical signs of puberty (a total of 76 serum profiles). Serum 17 beta-estradiol concentrations were determined using a modified RIA. The detection limit for the RIA was 1.8 fmol/tube, which corresponded to a serum level of 7.8 pmol/L in extracted serum. It was considered that levels above 50 pmol/L could be determined accurately without extraction. The serum levels of 17 beta-estradiol in prepubertal girls were, in most cases, below the detection limit, except in the morning, when in 17 of the 21 prepubertal girls, serum 17 beta-estradiol levels were just above the detection limit. All girls in early puberty (Tanner breast stage 2) had measurable serum levels of 17 beta-estradiol in the morning, whereas 10 of these 15 girls had levels below the detection limit around midnight. Later in puberty (Tanner breast stages 3 and 4), but before menarche, the diurnal rhythm was more obvious, with high levels of 17 beta-estradiol during the latter part of the night and in the morning. This diurnal rhythm was lost by 1 yr after menarche. There was a high degree of correlation between serum concentrations of 17 beta-estradiol and bone age, whereas there was much less, if any, correlation between 17 beta-estradiol and levels of sex hormone-binding globulin or dehydroepiandrosterone sulfate during puberty. We conclude that the nocturnal rise in gonadotropin secretion during puberty in girls is accompanied by an increased secretion of 17 beta-estradiol in the morning. This diurnal rhythm is lost 1 yr after menarche. Determination of 17 beta-estradiol levels in the morning could be useful in determining the initiation of puberty, whereas determinations in the late evening could provide information on the tempo of puberty.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Age Determination by Skeleton
  • Age Factors
  • Child
  • Circadian Rhythm / physiology*
  • Dehydroepiandrosterone Sulfate / blood
  • Estradiol / blood
  • Estradiol / metabolism*
  • Female
  • Humans
  • Hydrocortisone / blood
  • Male
  • Menarche / blood
  • Menarche / physiology
  • Puberty / blood
  • Puberty / physiology*
  • Radioimmunoassay / methods
  • Radioimmunoassay / statistics & numerical data
  • Sensitivity and Specificity
  • Sex Hormone-Binding Globulin / metabolism

Substances

  • Sex Hormone-Binding Globulin
  • Estradiol
  • Dehydroepiandrosterone Sulfate
  • Hydrocortisone