The ratio of the second to the fourth digit (2D:4D ratio) is a sexually dimorphic trait established in utero that differs between ethnic groups. It is associated with prenatal androgen exposure ...

We aimed to assess whether 2D : 4D measures are associated with breast cancer risk. We derived the ratio of the lengths of the index and ring fingers (2D : 4D), and right minus left 2D : 4D (Δr ...