Sexual maturation in Thai boys.
BACKGROUND
A worldwide secular trend towards earlier onset of puberty in girls has been noted during recent years. However, the data on sexual maturation of boys are relatively scarce and normative data of sexual maturation in Thai boys are still lacking.


OBJECTIVE
To determine the age of secondary sexual maturation in normal Thai boys.


METHODS
Three hundred healthy urban boys aged 9-18 years were recruited during January 1997 to December 1999. Genital and pubic hair maturity staging was determined using the method of Marshall and Tanner. Testicular size was assessed by Prader orchidometer. Probit analysis was used to analyze the onset of puberty (gonadarche) and pubarche.


RESULTS
Median (range) ages of the onset of puberty and pubarche were 10.8 (9.5-12) and 12.4 (10.9-13.9) years, respectively.


CONCLUSIONS
The age of onset of genital development in boys living in Bangkok seems to be slightly earlier than that of boys in other countries. However, the onset of pubic hair development is comparable.
Mahachoklertwattana
P
P
Department of Pediatrics, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand. rapmw@mahidol.ac.th
Suthutvoravut
U
U
Poomthavorn
P
P
Charoenkiatkul
S
S
Udomsubpayakul
U
U
Rajatanavin
R
R
D000293:Adolescent; D041923:Adolescent Development; D001827:Body Height; D001835:Body Weight; D002648:Child; D002657:Child Development; D005837:Genitalia, Male / Q000254:growth & development*; D006801:Humans; D008297:Male; D011627:Puberty; D012727:Sex Characteristics; D013785:Thailand; D014505:Urban Population