College of Massage Therapists of British Columbia (CMTBC) Practice Exam

What happens to tidal volume during pregnancy?

1. No change

2. Increase

3. Decrease

4. What do the ocean and pregnancy have to do with each other?

The correct answer is: Decrease

During pregnancy, tidal volume actually increases. This change is primarily due to the physiological adaptations that occur in a woman's body to accommodate the growing fetus and meet the increased metabolic demands of both the mother and the developing baby. As the uterus expands, it pushes against the diaphragm, but hormonal changes, such as increased levels of progesterone, enhance the respiratory drive and allow for greater lung expansion despite the space constraints. The increase in tidal volume contributes to improved oxygen exchange and ensures that the mother is able to deliver sufficient oxygen to the fetus while also removing carbon dioxide effectively. The other options do not accurately reflect the physiological changes that occur during pregnancy. While some individuals may feel breathless or notice a difference in their breathing patterns, the overall effect on tidal volume is an increase, making the understanding of respiratory changes during pregnancy crucial for practitioners working with expectant mothers.