Why do pregnant women waddle? Science now has the answer

Joking about ‘waddling’ while you are pregnant is like a rite of passage for every mother-to-be, but scientists now says that pregnant ‘waddling’ is actually biologically accurate.

So why do we waddle? The answer, as with most things to do with pregnancy, lies with hormones. While in the first trimester, hormones make your joints loosen in order to allow otherwise tight muscles to stretch to accommodate your little bundle of joy.

“Joint laxities make the lower part of the spine looser and more unstable,” says Myra Wick, MD. This includes muscles used for walking like those that support the spine – your muscles accommodate that by allowing muscles to shift unlike they usually would. “That can cause muscle strain and make you waddle,” she continues.

You can also blame your baby on making you waddle. As your baby grows, your baby’s weight changes the centre of gravity inside your body, shifting it so much that the mother must accommodate, mostly through that unique waddling we all know so well.

In a study conducted by Hiroshima University’s Professor Koichi Shinkoda in Japan, his team used 3D motion capture technology, the same as the technology used to bring the film Avatar to life, to record and analyse pregnant women’s movements. They used the information captured to create a virtual model of the average pregnant woman and how babies are carried.

Why study waddling? Yasuyo Sunaga, a member of the research team, says “we want to find the ideal way for new mothers to carry their baby” in the hope that they can apply what they find to problem-solve the concerns of a pregnant mother’s day-to-day life.