Scientist’s in the US think they’ve found the answer: There’s are slight differences between women and men in one lower back vertebrae and a joint in the hip, which allow women to adjust their center of gravity.
Harvard anthropology researcher Katherine Whitcomb found two physical differences in male and female backs that until now had gone unnoticed: One lower lumbar vertebrae is wedged-shaped in women and more square in men; and a key hip joint is 14 percent larger in women than men when body size is taken into account.
The researchers did engineering tests that show how those slight changes allow women to carry the additional and growing load without toppling over – and typically without disabling back pain.
There you go ladies, no matter how big you get, your body is engineered to handle that extra stress. I wonder is that still rings true for moms of mega multiples (4, 5 or 6 babies in utero)?