Marriage rate differences have already been shown to be correlated with hormone levels.[1][2] Measuring whether such a difference exists for the level of exposu

Marriage rate differences have already been shown to be correlated with hormone levels.[1][2] Measuring whether such a difference exists for the level of exposure in-utero simply by having a male twin is interesting. If anything, the natural interpretation of this data would be to expand the range of behavior (marriage rate) considered 'typical' for females. Similarly, fertility differences have been observed already for e.g. mice exposed to different levels of testosterone in utero. The 'freemartin' cows mentioned by another poster here are infertile for a similar reason. Hormones play a huge role developmentally and are almost 100% responsible for morphological sexual anatomy. There's no agenda present in measuring these outcomes. These are exactly the outcomes that would be expected naturally to be different. If anything, the unusual inclusion is the economic and educational factors. 1: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5501487/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5501487/ 2: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3540120/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3540120/