Twins are very much in our consciousness at the moment…because we are living through a twin boom. A higher proportion of human beings are twins than at any other time in living memory.
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To put it another way, the twinning rate is a highly sensitive indicator of biological and social change.
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A mother’s age was…the biggest single determinant of the twinning rate for most of the human story…That’s because blood levels of follicle-stimulating hormone…increase with age,…increasing the likelihood that more than one egg will be released in a given cycle…
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The current twin boom [took off]…with the advent of assisted reproductive technology (ART) – the umbrella term for fertility treatments that…increas[es] the chances that more than one embryo will be implanted at a time…The two main factors are ART and maternal age…
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If fertility treatments become more affordable, and neonatal healthcare improves, sub-Saharan Africa might see a ART-fuelled boom,…while the Chinese twinning rate is likely to increase as the one-child (per family) policy is phased out, and more and more Chinese people are lifted out of poverty.
The GLP aggregated and excerpted this blog/article to reflect the diversity of news, opinion and analysis. Read full, original post: The twin boom