A Harvard scientist has put forward a daring hypothesis that as well as being hungry, or wet nappied, or gassy - babies demand attention in the middle of the night as an attempt to stop mum getting pregnant again.
David Haig claims in his article, published in Evolution, Medicine, and Public Health, that babies who tend to distrupt their parents in the night, thus keeping their mum (in particular) tired, are doing it on purpose to prevent another baby from appearing and hogging all their resources.
He also adds that in breastfed babies in particular, the hormones required to produce milk tend to have a dampening effect on ovulation which - while not foolproof - means that were the exhausted mama likely to feel the urge to have sex, the liklihood of her becoming pregnant are again limited.
While there have been no studies to prove the relationship between these factors, Haig considers the idea of babies-interrupting-their-parents-so-they-can't-get-laid a promising one - and any parent with a newborn could hardly deny it might very well be doing the trick.
This article first published on New Idea.