The fragile male

BMJ 2001; 322 doi: https://doi.org/10.1136/bmj.322.7286.617/a (Published 10 March 2001) Cite this as: BMJ 2001;322:617

Male zygotes are often formed at suboptimal times in fertile cycle

  1. William H James, honorary research fellow
  1. Galton Laboratory, University College London, London NW1 2HE
  2. Men's Health Forum, London WC1H 9JP

    EDITOR—Kraemer adduced large quantities of data to substantiate the proposition that, from conception, males are more vulnerable than females.1 Postnatal vulnerability has some social causes, which are known, but the causes of the prenatal vulnerability of males are not established, so I wish to suggest one.

    During the menstrual cycle women have a fertile window lasting several days.2 There is strong direct3 and indirect4 evidence that the regression of the sex ratio of the offspring (proportion male) on the time of fertilisation is U shaped across this fertile window. In other words, females are formed disproportionately often in the middle of this window and males at either end of it. There is also strong evidence that zygotes formed at either end of the window are more likely to be spontaneously aborted.5

    Thus it would seem that, compared with female zygotes, male zygotes are formed disproportionately often at suboptimal times in the cycle. This suggestion would explain three factors: the additional prenatal vulnerability of males, the suspected higher sex ratio in spontaneously aborted fetuses than in live births, and the male excesses in those adult diseases suspected of being related to suboptimal intrauterine environments.


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    Men should follow example of women's health movement

    1. Ian Banks, chairman (ian{at}medic40.freeserve.co.uk)
    1. Galton Laboratory, University College London, London NW1 2HE
    2. Men's Health Forum, London WC1H 9JP

      EDITOR—As Kraemer points out, being a man can seriously damage your health.1 The Men's Health Forum (http://www.menshealthforum.org.uk/), with a membership of over 180 organisations ranging from the BMA and the Department of Health to the Royal College of Nursing, and from the Post Office to Marks and Spencer, has campaigned on this issue for six years. Politicians now seem to realise that men's health is often a contradiction in terms and urgently needs more attention and resources.

      Extensive research shows that the health of both sexes is often inextricably entwined; this is clearly shown by chlamydial infection. A joint approach to the health of women and men is required, rather than a “them and us” confrontation.

      It is no coincidence that men's health is increasingly highlighted in areas where women are taking their place as policymakers. Half of the elected representatives of the Men's Health Forum are female, with a woman as deputy chair. It was two women—Tessa Jowell and Yvette Cooper (minister for public health and minister for health, respectively)—not Frank Dobson or Alan Milburn (previous and current health secretaries) who brought men's health as an issue to the attention of parliament.

      Perhaps men should take a leaf from the women's health movement's book rather than begrudge women their success. With spending on women's health in the United Kingdom the lowest in Europe, it would serve both sexes well to improve spending generally in the NHS.


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