What is the phenomenon of opening the joints when giving birth?

Patient's question:

No

Doctor's answer:

Hello: During pregnancy, the common folk say that giving birth involves "opening the bone gaps." We argue that this statement is not scientific; what actually happens is the dilation of the cervix. However, during pregnancy, the ligaments in our joints loosen due to the changes pregnancy brings, causing this relaxation. That's why we measure the mother's pelvis before birth—it's because the ligaments haven't fully loosened yet in the second trimester.
We say that ligament relaxation might cause some people to feel joint swelling when moving or hear a popping sound when they roll over. This is primarily due to the ligament relaxation during pregnancy.