What physiological change is associated with pregnancy in regard to tidal volume?

During pregnancy, hormonal and anatomical changes lead to significant physiological adaptations, particularly in the respiratory system. One of the key changes is an increase in tidal volume, which is the amount of air that is inhaled or exhaled during normal breathing.

The correct answer highlights that this increase is approximately 40%. This increase is primarily driven by the need for enhanced oxygen delivery to both the mother and the developing fetus, as metabolic demands rise. Increased tidal volume also helps to compensate for the decreased functional residual capacity due to the upward displacement of the diaphragm by the enlarging uterus.

By increasing tidal volume significantly, the body ensures that adequate gas exchange occurs despite these anatomical changes. Additionally, this adjustment works in conjunction with other physiological changes during pregnancy, such as increased respiratory rate and changes in the acid-base balance, to optimize respiratory function for both maternal and fetal health.