2nd to 4th digit ratios, fetal testosterone and estradiol.

  title={2nd to 4th digit ratios, fetal testosterone and estradiol.},
  author={Svetlana Lutchmaya and Simon Baron-Cohen and Peter Raggatt and Rebecca Knickmeyer and John T. Manning},
  journal={Early human development},
  volume={77 1-2},
BACKGROUND The ratio of 2nd to 4th digit length (2D:4D) is sexually dimorphic (mean 2D:4D is lower in males than females) and is thought to be fixed early in development. 2D:4D has been reported to be related to fetal growth, hand preference, autism, Asperger's syndrome, sperm counts, family size, age at myocardial infarction in men and breast cancer in… CONTINUE READING