Stress sparks 'male foetus death'

A woman's body may actively kill off weaker male foetuses during times of stress, research suggests.

It is known that fewer boys tend to be born during times of hardship, such as a natural disaster.

Male foetuses and embryos are weaker than females and are less likely to survive to birth. It is not known why this should be the case.

Writing in Proceedings of the National Academy of Sciences researchers concluded aborting boys may be a way to maximise the odds of survival of the bloodline.

Two explanations have been suggested as to why the proportion of newborn boys often dips sharply during times of stress.

One is that a mothers' stress responses damage their unborn babies, affecting already weaker males disproportionately and spontaneously aborting more males than usual.

But a competing explanation is that mothers' bodies under stress have less tolerance for unhealthy embryos and foetuses, and thus spontaneously abort offspring that would have been otherwise carried to birth.

The scientists said their analysis supported the latter explanation.

more ...

Links:
Proceedings of the National Academy of Sciences
British Fertility Society

Makes sense to me ...