[Relation between endocrine changes and bodily development before and after the menarche]

Serum concentrations of sex hormones which including FSH, LH, prolactin (PRL), estradiol (E2), 17 alpha-hydroxyprogesterone (17OH-P4) and 17 alpha-hydroxypregnenolone (17OH-P5) were measured in 233 girls aged 6 to 17. For the longitudinal study, 31 girls aged 10 to 13 were selected and studied for two years to find out the relationship between hormonal changes and pelvic development. The subjects were divided into three groups: Group I; premenarchal girls, Group II; menarche occurred during the studied year, Group III; menarche had already occurred. 1) Changes of hormones with age: FSH and E2 concentrations started to increase from age 10 and LH increased from age 11. On the other hand, PRL concentration decreased from age 10 to 11 in menarchal girls. 2) Changes of hormones for 2 years: The elevation of FSH, LH, E2, 17OH-P4, DHA and 17OH-P5 was noticed in group I. A significant increase of E2 levels in group I and II was noted. On the other hand, concentrations of PRL in group II significantly decreased. 3) Physical development for 2 years: A significant elevation of physical development and outer dimensions of pelves in all groups was observed. However, increase of pelvic indices were significant in group II. 4) Relation between physical development and hormones: Except for PRL all the hormones increased before the onset of menarche and the continuous elevation of E2 was found with increasing age after menarche. These results suggested the possible role of E2 on pelvic development during puberty.