• Corpus ID: 27007732

Fraternal Birth Order and the Maternal Immune

@inproceedings{Blanchard2001FraternalBO,
  title={Fraternal Birth Order and the Maternal Immune},
  author={Ray Blanchard},
  year={2001}
}
increasing the odds of homosexuality by approximately 33%. It has been hypothesized that this fraternal birth order effect reflects the progressive immunization of some mothers to Y-linked minor histocompatibility antigens (H-Y antigens) by each succeeding male fetus and the concomitantly increasing effects of such maternal immunization on the future sexual orientation of each succeeding male fetus. According to this hypothesis, anti-H-Y antibodies produced by the mother pass through the… 

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