Archives of Sexual Behavior

, Volume 44, Issue 5, pp 1503–1509 | Cite as

Commentary on Kishida and Rahman (2015), Including a Meta-analysis of Relevant Studies on Fraternal Birth Order and Sexual Orientation in Men

  • Ray BlanchardEmail author
  • Doug P. VanderLaan
Invited Commentary


The term fraternal birth order effect refers to the finding that homosexual men, on average, have greater numbers of older brothers than do demographically comparable heterosexual men. This finding has been demonstrated in studies conducted in the U.K., the U.S.A., Canada, Finland, Independent Samoa, Italy, the Netherlands, Spain, and Turkey. Several articles have reviewed the history of this research area and summarized the evidence available at their time of publication (Blanchard, 1997, 2004, 2008; Bogaert & Skorska, 2011).

Kishida and Rahman (2015) recently published an empirical study of male sexual orientation in relation to subjects’ numbers of older brothers, hand-preference, and self-reported childhood effeminacy. They concluded, in regard to their comparisons of homosexual and heterosexual subjects on older brothers, that “The results did not replicate the fraternal birth order effect.” The purpose of this Commentary is to argue that Kishida and Rahman’s...


Sexual Orientation Birth Order Young Brother Gender Dysphoria Young Sister 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.Department of PsychiatryUniversity of TorontoTorontoCanada
  2. 2.Gender Identity Clinic, Child, Youth and Family ServicesCentre for Addiction and Mental HealthTorontoCanada

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