Many pregnant women who suffer from asthma are putting their unborn child’s health at risk by failing to use the right medication, according to a University of Adelaide researcher.
Postdoctoral researcher Dr Annette Osei-Kumah says if asthma is not correctly managed during pregnancy it can result in premature births, low birth weights and even stillbirths.
Dr Osei-Kumah, the University of Adelaide’s inaugural Florey Fellow, says asthma is often worse during pregnancy due to different factors released from the placenta which cause inflammation in the mothers’ lung.
Previous studies reveal that during pregnancy, one third of women report their asthma is worse, one third maintain their asthma remains the same and another third report an improvement.
However, most women underestimate the effect of asthma during their pregnancy, Dr Osei-Kumah says.
Asthma is the most common potentially serious medical condition to complicate pregnancy. In fact, asthma affects approximately 8 percent of women in their childbearing years. Well-controlled asthma is not associated with significant risk to mother or fetus. Uncontrolled asthma can cause serious complications to the mother, including high blood pressure, toxemia, premature delivery and rarely death. For the baby, complications of uncontrolled asthma include increased risk of stillbirth, fetal growth retardation, premature birth, low birth weight and a low APGAR score at birth.
Asthma can be controlled by careful medical management and avoidance of known triggers, so asthma need not be a reason for avoiding pregnancy. Most measures used to control asthma are not harmful to the developing fetus and do not appear to contribute to either miscarriage or birth defects.
Although the outcome of any pregnancy can never be guaranteed, most women with asthma and allergies do well with proper medical management by physicians familiar with these disorders and the changes that occur during pregnancy.
“Most women who said their asthma didn’t change actually recorded poorer lung function when tested and 55% experienced at least one asthma attack during pregnancy,” she says.
There are sex-specific effects as well. Uncontrolled asthma invariably leads to low birth weights in female babies. Male babies, on the other hand, continue to grow normally but if a mother has an asthma attack during pregnancy they are less likely to survive.
SEVERITY OF ASTHMA DURING PREGNANCY
The severity of asthma during pregnancy varies from one woman to another. Unfortunately, it is difficult to predict the course that asthma will follow in a woman’s first pregnancy. During pregnancy, asthma worsens in about one-third of women, improves in one-third, and remains stable in one-third.
Other patterns that have been observed include:
- Among women whose asthma worsens, an increase in symptoms is often seen between weeks 29 and 36 of pregnancy
- Asthma is generally less severe during the last month of pregnancy
- Labor and delivery do not usually worsen asthma
- Among women whose asthma improves, the improvement typically progresses gradually throughout pregnancy
- The severity of asthma symptoms during the first pregnancy is often similar in subsequent pregnancies
Factors affecting risk of attacks - The factors that increase or decrease the risk of asthma attacks during pregnancy are not entirely clear. The likelihood of these attacks is not constant throughout pregnancy; attacks seem to be most likely during weeks 17 through 24 of pregnancy. The cause for this pattern is unknown, although it may be because some women stop using asthma-controlling drugs when they realize they are pregnant, increasing their risk for attacks.
Dr Osei-Kumah says most women who are asthmatic stop using their medications during pregnancy due to fear of side effects, but their concerns are unfounded.
“What we have found is the lack of medication use is leading to problems, aggravating the asthma and putting the fetus as risk, as well as the mother’s health.