Effects of prenatal Leydig cell function on the ratio of the second to fourth digit lengths in school-aged children.
Prenatal sex hormones can induce abnormalities in the reproductive system and adversely impact on genital development. We investigated whether sex hormones in cord blood influenced the ratio of the second to fourth digit lengths (2D/4D) in school-aged children. Of the 514 children who participated in a prospective cohort study on birth in Sapporo between 2002 and 2005, the following sex hormone levels were measured in 294 stored cord blood samples (135 boys and 159 girls); testosterone (T), estradiol (E), progesterone, LH, FSH, inhibin B, and insulin-like factor 3 (INSL3). A total of 350 children, who were of school age and could be contacted for this survey, were then requested via mail to send black-and-white photocopies of the palms of both the left and right hands. 2D/4D was calculated in 190 children (88 boys and 102 girls) using photocopies and derived from participants with the characteristics of older mothers, a higher annual household income, higher educational level, and fewer smokers among family members. 2D/4D was significantly lower in males than in females (p<0.01). In the 294 stored cord blood samples, T, T/E, LH, FSH, Inhibin B, and INSL3 levels were significantly higher in samples collected from males than those from females. A multivariate regression model revealed that 2D/4D negatively correlated with INSL3 in males and was significantly higher in males with <0.32 ng/mL of INSL3 (p<0.01). No correlations were observed between other hormones and 2D/4D. In conclusion, 2D/4D in school-aged children, which was significantly lower in males than in females, was affected by prenatal Leydig cell function.
Department of Urology, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan.
Takahiko
T
Mitsui
Hokkaido University Center for Environmental and Health Sciences, Sapporo, Hokkaido, Japan.
Atsuko
A
Araki
Department of Urology, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan.
Ayako
A
Imai
Department of Urology, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan.
Sakiko
S
Sato
Hokkaido University Center for Environmental and Health Sciences, Sapporo, Hokkaido, Japan.
Chihiro
C
Miyashita
Hokkaido University Center for Environmental and Health Sciences, Sapporo, Hokkaido, Japan.
Sachiko
S
Ito
Department of Public Health, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan.
Seiko
S
Sasaki
Department of Urology, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan.
Takeya
T
Kitta
Department of Urology, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan.
Kimihiko
K
Moriya
Department of Obstetrics and Gynecology, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan.
Kazutoshi
K
Cho
Department of Obstetrics and Gynecology, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan.
Keita
K
Morioka
Hokkaido University Center for Environmental and Health Sciences, Sapporo, Hokkaido, Japan.
Reiko
R
Kishi
Department of Urology, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan.
Katsuya
K
Nonomura
D000328:Adult; D002648:Child; D005260:Female; D005312:Fetal Blood; D005385:Fingers / Q000033:anatomy & histology / Q000254:growth & development*; D012739:Gonadal Steroid Hormones / Q000097:blood*; D006801:Humans; D007231:Infant, Newborn; D007985:Leydig Cells / Q000378:metabolism*; D008297:Male; D008954:Models, Biological; D009929:Organ Size / Q000502:physiology; D011247:Pregnancy; D011446:Prospective Studies
D012739:Gonadal Steroid Hormones