How does pregnancy affect the biomechanics of the chest wall?

What will be an ideal response?

ANS: Progressive uterine distention repositions the diaphragm cephalad with a resultant increase in chest
circumference. The change in circumference is due to many factors, including enhanced
diaphragmatic contraction due to improved length-tension relationship and increased area of
diaphragmatic apposition. During pregnancy, there is a measurable decrease in functional residual
capacity, but vital capacity does not change.