What are the causes of asthma in pregnant women?

Pregnant women are prone to chest tightness and shortness of breath during pregnancy, especially in the later stages of pregnancy. Respiratory diseases are most likely to occur. The reasons for shortness of breath in pregnant women include not only the uterus compressing the chest tightness and respiratory system, but also many other factors. You need to pay attention to judgment and choose appropriate treatment methods in normal times.

Increased progesterone causes breathlessness

The increase in hormones during pregnancy, especially the increase in progesterone (also known as progesterone), can directly affect the lungs and stimulate the respiratory center in the pregnant woman's brain. According to statistics, the number of breaths per minute taken by pregnant women does not change much, but the amount of air inhaled will increase significantly, causing shortness of breath.

Rapid metabolism leading to shortness of breath

Various changes in the mother's body and the growth and development of the fetus during the second trimester increase the workload of the mother's tissues and organs and speed up metabolism. The fetus relies on the mother's oxygen supply, so pregnant women must increase lung ventilation (about 40% more than non-pregnant period). This causes pregnant women to hyperventilate and feel shortness of breath. Don't be afraid of this, just pay attention to practice and adjust.

The enlarged uterus affects breathing

In the later stages of pregnancy, as the pregnant uterus grows, it presses upward on the diaphragm, thereby reducing the volume of the thoracic cavity and decreasing diaphragm activity, causing pregnant women to become short of breath and feel breathless and chest tightness. This is a normal phenomenon. As long as you pay attention to proper rest and avoid overwork, the shortness of breath will disappear after delivery.

Increased circulating blood volume leading to shortness of breath

In early pregnancy, there are symptoms of shortness of breath and chest tightness. This is because the maternal blood volume increases by an average of 1500 ml compared to the non-pregnant period. The increase in plasma far exceeds the increase in red blood cells, resulting in physiological anemia of pregnancy, which causes the blood's oxygen-carrying capacity to decrease. In addition, the enlarged uterus causes the heart to shift upward and to the left, and the heart works under unfavorable conditions. All of the above factors increase the burden on the heart. When the amount of activity increases and the oxygen demand increases, it is easy to experience palpitations and shortness of breath. Experts say that if there is no organic disease in the heart, there will be no major hindrance.