Not the actual babies, but the birth weight of the new ones.
Just a snippet; I’ve not looked into this yet. But given that human size goes up and down over secular time, this probably would mean (if it means anything at all) that we’ve peaked out with whatever causes that cycle:
Birthweights in the US are falling but no one knows why, according to a study of 36.8 million infants born between 1990 and 2005.
A 52-gram drop in the weight of full-term singletons – from an average of 3.441 to 3.389 kilograms – has left Emily Oken’s team at Harvard Medical School scratching their heads.