One of the main concerns during the stage of pregnancy where there is a proper supply of oxygen to both the mother and the baby. A host of physiologic changes tend to take place during the stage of pregnancy that can pave way for pregnancy respiratory disorders and tamper with the ability to deliver oxygen to the lungs. You would need to consider changes to the cardiovascular, endocrine and the respiratory tract itself.
The changes of the endocrine system
During the course of pregnancy, the endocrine witnesses massive changes, in the level of cortisol and estrogen. The levels of estrogen are known to rise in the starting stages of pregnancy, and it is an above normal level till the time of delivery. When the level of this hormone, is elevated it goes on to produce increased red blood mass. An increase in the levels of blood is needed for the extra blood to be able to flow on to the uterus and in the process meet the excess metabolic needs of the fetus.
The concentration of progesterone also does increase in the starting stages of pregnancy, and this remains at a stage of elevation during the time of delivery. An increase of it would mean an increase in the stimulation of the respiratory centre, but it does pave way for bronchial smooth relaxation as well.
The concentration of cortisol also increases at this point of time. An increase in the level of free or total levels of this hormone is being observed. It in no way does indicate that the increase of it is going to reduce the severity of asthma in this regard.
Changes in the respiratory system
A trend that is observed that the respiratory system too undergoes physiologic and anatomic changes, during the times of pregnancy. Some of the changes would include a change in the formation of chest wall, elevation of diaphragm. All these changes are going to have an impact on the measurements of your lung.
One of the measurements that you would need to be aware is minute ventilation. It is a combination of respiratory volume and the tidal volume. Some other areas of pulmonary status work out to be the lung capacities along with volumes. Both of them tend to be four in number whereas some of them tend to undergo some minor changes during the course of pregnancy. This could be the case if you do not have asthma as well. The inspiratory volume of respiratory does remain unchanged in consortium with the vital capacity. The lung capacity could be slightly changed or decrease at a minimum level. All of these indicate that the pulmonary functions is altered during the stage of pregnancy, there is no compromise and in the lack of any form of respiratory condition no stress on the mechanical efficiency of the respiratory tract is assured. There are numerous medicines for respiratory disorders in pregnancy which might work wonders at this juncture.