Research article

Salivary testosterone levels in preadolescent children

Daniela Ostatníková¹ , Karol Pastor² , Zdenek Putz³ , Monika Dohnányiová¹ , Anna Mat'ašeje¹ and Richard Hampl⁴

¹  Institute of Physiology, School of Medicine, Comenius University, Bratislava, Slovak Republic

²  Department of Probability and Statistics, Faculty of Mathematics and Physics, Comenius University, Bratislava, Slovak Republic

³  Institute of Endocrinology, L'ubochòa, Slovak Republic

⁴  Institute of Endocrinology, Praha, Czech Republic

author email corresponding author email

BMC Pediatrics 2002, 2:5doi:10.1186/1471-2431-2-5

Published:	3 June 2002

Abstract

Background

Saliva reflects the plasma free fraction of testosterone which is biologically active, and available for uptake by tissues. Testosterone concentration in saliva, though differing slightly from the concentration of unbound testosterone in serum, is in good correlation with the latter, indicating that salivary testosterone provides a reliable method for determination of serum free testosterone. The study aimed to investigate salivary testosterone levels and their changes in preadolescent children and to study sexual dimorphism.

Methods

Testosterone levels were determined in 203 healthy preadolescent children (77 girls and 126 boys) from saliva samples by radioimmunoassay. Sampling was performed once a year with respect to circadian and seasonal fluctuations of testosterone. Data were statistically analyzed by Statgraphic software.

Results

Mean salivary testosterone concentrations (± SD) were 0.038 ± 0.012 nmol/L and 0.046 ± 0.026 nmol/L for girls and boys, with the medians 0.035 nmol/L and 0.041 nmol/L, respectively. Statistical analysis did not prove changes in salivary testosterone concentrations in the preadolescent period of life, with an exception of the insignificant fall at the age of 7 years, and an insignificant rise at the age of 9 years in girls.

Conclusions

Generally it can be concluded that salivary testosterone levels in our prepubertal subjects remained stable. There was no significant increase of salivary testosterone levels from the age of 6 until the age of 9 in both sexes. Sexual dimorphism in salivary testosterone levels was proved with significantly higher (p = 0.009) salivary testosterone levels in boys than in girls.