Document Detail

The cause(s) of the fraternal birth order effect in male homosexuality.
MedLine Citation:
PMID:  14989531     Owner:  NLM     Status:  MEDLINE    
It has been established that the probability that a man is homosexual is positively related to his number of older brothers, but not older sisters when the brothers are accounted for. This is known as the 'fraternal birth order' effect. In the past, efforts have been made to explain this phenomenon in terms of several alternative biological hypotheses and a psychosocial hypothesis. This note examines how well these hypotheses accommodate the fraternal birth order effect. It is concluded that: (1) the evidence for the hypothesis of maternal immunoreactivity to the male fetus is weak; (2) the evidence for the intrauterine hormone exposure hypothesis is also weak; (3) the evidence for the hypothesis of postnatal learning is stronger. Lastly, there seem likely to be causes common to male homosexuality and paedophilia. They may include sexual (or quasi-sexual) experience in childhood or adolescence.
William H James
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Journal of biosocial science     Volume:  36     ISSN:  0021-9320     ISO Abbreviation:  J Biosoc Sci     Publication Date:  2004 Jan 
Date Detail:
Created Date:  2004-03-01     Completed Date:  2004-05-11     Revised Date:  2004-11-17    
Medline Journal Info:
Nlm Unique ID:  0177346     Medline TA:  J Biosoc Sci     Country:  England    
Other Details:
Languages:  eng     Pagination:  51-9, 61-2     Citation Subset:  IM    
The Galton Laboratory, University College London, Wolfson House, 4 Stephenson Way, London NW1 2HE.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Birth Order*
Homosexuality, Male*
Prenatal Exposure Delayed Effects

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Determinants of pill failure in rural Bangladesh.
Next Document:  Schistosomiasis-related perceptions, attitudes and treatment-seeking practices in Magu district, Tan...