Asthma is one of the most common medical conditions that complicates pregnancy. Approximately 8 percent of women develop asthma in their childbearing years, according to the American College of Allergy, Asthma and Immunology. Well-controlled asthma presents little risk to a mother or her unborn child, but uncontrolled asthma may cause a multitude of pregnancy complications such as high blood pressure, increased risk of stillbirth, fetal growth retardation and premature birth.
Premature Birth
Pregnant women who have poorly controlled asthma are at risk for premature birth, which is a birth that occurs before the 37th week of pregnancy, according to the March of Dimes. Asthma occurs when a person’s bronchial tubes, the tubes that carry air in and out of the lungs, narrow due to inflammation, causing labored breathing. Women with chronic illnesses such as asthma are more likely to have extra stress on their bodies during pregnancy compared with women who are healthy. The added stress puts pressure on the fetus, triggering a premature birth. In addition, Asthma UK states that women who are hospitalized because of asthma during their pregnancies are more likely to give birth prematurely.
Preeclampsia
Asthmatic women may experience preeclampsia during pregnancy if their asthma is not controlled. Preeclampsia, also called toxemia, occurs when a pregnant woman’s blood pressure increases, she retains fluid and she produces excess protein in her urine, according to the New York Presbyterian Hospital. Asthmatic women with moderate to severe symptoms during pregnancy are more likely to develop preeclampsia than are women without a history of asthma, according to the website Pregnancy.org. There is also a risk that an asthmatic woman may develop eclampsia, a condition that causes rapid swelling in the brain’s membrane, resulting in multiple seizures. The only way to treat eclampsia is by immediate delivery, usually by cesarean section.
Delayed Fetal Growth
Another pregnancy complication associated with asthma is delayed fetal growth. Southwest Asthma and Allergy Associates state that a fetus requires a continuous supply of oxygen for normal growth and development. When a woman’s asthma is poorly controlled, the amount of oxygen in her blood steadily declines, depriving her fetus of oxygen and preventing or delaying fetal development. After birth, the babies of women with asthma tend to be smaller than those of women who do not have a history of the condition.
References
- The Southwest Asthma and Allergy Associates: Asthma and Pregnancy
- March of Dimes: Asthma and Pregnancy
- American College of Allergy, Asthma and Immunology: When Pregnancy is Complicated by Allergies and Asthma
- Asthma UK: Premature Births Linked to Poor Asthma Control in Mothers
- New York Presbyterian Hospital: Asthma and Pregnancy
