Second to fourth digit length ratio (2D:4D) and adult sex hormone levels: New data and a meta-analytic review

@article{Hnekopp2007SecondTF,
  title={Second to fourth digit length ratio (2D:4D) and adult sex hormone levels: New data and a meta-analytic review},
  author={Johannes H{\"o}nekopp and Luise Bartholdt and Lothar Beier and Andreas Liebert},
  journal={Psychoneuroendocrinology},
  year={2007},
  volume={32},
  pages={313-321}
}

Tables from this paper

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Digit ratio (2D:4D) as an indicator of body size, testosterone concentration and number of children in human males
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It is shown, for the first time in a single population, that digit ratio is related to sub-adult body size at different stages of the life course, adult testosterone levels and number of children.
Digit ratio (2D:4D) and Congenital Adrenal Hyperplasia (CAH): Systematic Literature Review and Meta-Analysis
TLDR
A systematic review of 2D:4D in people with congenital adrenal hyperplasia found no evidence to suggest the right-left difference in 2D:[R-L]) is associated with prenatal sex hormone exposure, and the effect size had reduced by 46.70%.
Digit length ratio (2D:4D) and variation in key life-history traits and fitness in contemporary Finnish women
TLDR
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References

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2nd to 4th digit ratio (2D:4D) and number of sex partners: Evidence for effects of prenatal testosterone in men
The second to fourth digit ratio and asymmetry
TLDR
The data show that both low 2D:4D and high 2D :4D are associated with elevated levels of asymmetry and this relationship applies particularly to finger asymmetry.
Second to fourth digit ratio (2D:4D) and testosterone in men.
TLDR
Adult levels of testosterone may be related to aspects of 2D:4D in samples which contain men with compromised testicular function, but not in men from normative samples.
2nd to 4th digit ratios, fetal testosterone and estradiol.
The ratio of 2nd to 4th digit length: a predictor of sperm numbers and concentrations of testosterone, luteinizing hormone and oestrogen.
TLDR
It is shown that 2D:4D in right and left hands has a sexually dimorphic pattern and is probably established in utero, which raises the possibility that patterns of digit formation may relate to spermatogenesis and hormonal concentrations.
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