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Br Med J. Sep 13, 1980; 281(6242): 711–712.
PMCID: PMC1713947

Gonadotrophin and the human secondary sex ratio.


A review of published reports showed that the sex ratio (proportion of boys) was low among infants conceived after ovulation had been induced. The difference between the observed sex ratio and an expected one of 0 . 514 was highly significant. These findings suggest that maternal gonadotrophin concentrations at the time of conception directly affect the sex of the zygote.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.
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