It's being dubbed 'childhood contagion' where we become particularly broody when faced with our nearest and dearest doing it first.
It's basically a type of pregnancy peer pressure scenario...
One of the researchers from the study said:
"It shows that high school friends impact our lives well after graduation...we know that friends influence each other on many behaviors, such as smoking, drinking, and how much we exercise."
In the study the average age of a woman having her first bubba was 27 and apparently, according to the experts having children at the same time as your chums means the experience can be shared, easing all the pregnancy stresses and strains we girls suffer.
So, it seems all quite positive really.
So, is this why a load of celebs are all expecting little ones, then?
Well, it all makes sense now...
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