Do Mothers Create Gay Sons In The Womb?
A new study by Anthony F. Bogaert of Brock University (Canada) claims his research has found a biological basis for homosexuality in young men with older brothers.
June 29, 2006 - A new study by Anthony F. Bogaert published by the
Proceedings of the National Academy of Sciences (July 11, 2006) is being promoted worldwide as evidence of a biological basis of homosexuality in young men with older brothers.
The study, "Biological versus nonbiological older brothers and men's sexual orientation," surveyed the family histories of 944 homosexual and heterosexual males, including samples of males reared with half- or step-siblings or as adoptees. According to Bogaert: "Only biological older brothers, and not any other sibling characteristic, including non-biological older brothers, predicted men's sexual orientation, regardless of the amount of time reared with these siblings. These results strongly suggest a prenatal origin to the fraternal birth-order effect."
In a news story published by the gay Washington Blade magazine, Bogaert was quoted as saying: "It's likely to be a prenatal effect. This and other studies suggest that there is a probably a biological basis" for homosexuality.
Bogaert suggests in his study:
A theory of male homosexuality consistent with the present findings is a maternal immune response to succeeding male pregnancies. This explanation is partly based on the idea that a woman's immune system would appear to be capable of remembering the number of male fetuses she has previously carried and of progressively altering its response to the next fetus according to the current tally of preceding males. A mother's body may have a memory for male (but not female) fetuses because she herself is female, and thus, her immune system may interpret and remember male (but not female) fetuses as foreign. If this immune theory were correct, then the link between the mother's immune reaction and of the child's future sexual orientation would probably be some effect of maternal anti-male antibodies on the sexual differentiation of the brain."
Three professional members of NARTH have reviewed Bogaert's research study and have found significant flaws in it.
Canadian Psychiatrist Joseph Berger, Ph.D., is a Distinguished Fellow with the American Psychiatric Association, a member of NARTH's Scientific Advisory Committee and author of
The Independent Medical Examination in Psychiatry. Dr. Berger has observed:
This study is yet another claim based upon superficial research that may be purely coincidental to or entirely unrelated to the conclusion that the researchers are proposing.
There is a conceptual leap based upon nothing other than an obvious personal wish/bias, from what may be an interesting chance finding based upon a small population sample to a generalization about the etiology of homosexuality.
There is no substantive basis for any such link. It is far too early to do anything other than speculate about the possible causes of such a finding, if indeed repeated surveys with larger populations confirmed its accuracy.
There are obvious possible "environmental" explanations for such a finding, such as the tendency in many families to "baby" the younger or youngest, often thus "delaying" their maturity into an adult masculine identity. The tendency of many such younger/youngest children to play up the "cute" "wishing-to-please" baby-aspect, which can take on an almost feminine charming/seductive demeanor.
There are many alternative explanations to the findings. It is totally inappropriate for anyone to claim certainty in a study like this because such a claim is obviously political, not scientific in nature.
Dr. Neil E. Whitehead, a New Zealand research scientist has also review Bogaert's research study. He writes:
This [Bogaert] paper recruited from the gay community people with elder brothers to compare with heterosexual people with elder brothers. It also recruited heterosexuals from blended families, or families involving adoption and used archival samples. It confirmed a well-known effect in the literature - the more elder brothers a boy has, the higher the chance of same-sex attraction (SSA). The really interesting and novel point is that there was a similar prediction even if the subject had been brought up in a family isolated from those biological elder brothers. The author therefore argues the homosexuality cannot be a social effect peculiar to either family, and must be biological in origin.
Unfortunately, the method of recruitment may have invalidated this study. It is already known from twin studies research that samples recruited from the gay/lesbian community are liable to greatly exaggerate biological input because of the volunteer effect, which is found in studies of communities of many descriptions. Those twin pairs who were intrigued that both of them were gay volunteered in such large numbers that it badly affected the results of several older studies. This was shown by later results from twin pairs recruited from the general population for more general research purposes. The latter results were very different from the gay-recruited studies, and this effect could have affected the present study.
In the case of the present paper, it is very likely that volunteers were intrigued they were gay in spite of being adopted and knowing the nature of the study volunteered disproportionately—the more biological brothers they had. This would give the effect the author found, but does not necessarily reflect reality. Nor does the author seem to have allowed for the fact that adoption itself is one factor in development of SSA. This means the study cannot be taken very seriously until confirmed by a proper population-based (truly random) rather than a gay community-based sample. There is a serious doubt that the finding is valid.
Bogaert does not give enough information about the adoptions. It could be that adoptions were mostly extremely early before there could be any social influence of the biological family. That would strengthen the author's case for biological influences. But it could also be that most were mid-childhood or later (long-term fostering and divorces, for example) and sexual orientation was already established. The author finds no connection between SSA and years with either non-biological or biological brothers. But this broad statistic could easily hide crucial confounding data.
I am also concerned about the statistics with some aspects of the modeling. Fitting a model with 18 variables and 378 subjects weakens the statistical power so much that the result will have a large error, and the author does not present an analysis of how bad this effect is.
The author goes on to strongly press the case not just for a biological origin of SSA but a maternal immune hypothesis. This hypothesis has at least four speculative layers to it, and requires much better evidence before it gains general acceptance.
Finally, it should be remembered that most gays do not have elder brothers. The present theory tries to explain the SSA of perhaps as low as 17% of the total. The SSA of the others must arise from other sources.
The paper in no way warrants the media frenzy it has generated, particularly the headlines which argue that SSA is already fixed in the womb.
Family counseling Psychiatrist Dr. Richard Fitzgibbons also has concerns about Bogaert's claims. He writes:
In my clinical experience a major issue in regard to older brothers is the rejection a younger brother often experiences from older male siblings. This is particularly the case when the younger brother is not good in sports and is called cruel names by the older brother.
The other important dynamic here is that older brothers often misdirect anger meant for an emotionally distant, angry, selfish, controlling father at a younger brother. The younger brother then experiences rejection by two very important males in his life. These traumatic events severely weaken male confidence, which is the major emotional conflict leading to SSA.
Finally, some older brothers sexually abuse a younger brother, which can be another issue in the development of SSA.
Fortunately, these brother and father wounds can be healed through the hard work of an understanding and forgiveness process, growth in male confidence and growth with a spiritual director in the relationship with the Lord as best friend and brother at each life stage.
