by Christine Haran
Women who are pregnant are generally advised not to take any medication to avoid exposing the fetus to potentially harmful chemicals. So it's not uncommon to find a pregnant woman struggling with a sinus infection because she wants to avoid antibiotics, or a headache because she's not taking aspirin. But asthma is a different story. Studies suggest that women with untreated asthma are more likely to have problems with their pregnancies -- and that women with asthma should be treated for it during pregnancy.
There has been concern that the use of inhaled steroids, which are used to treat persistent asthma, during pregnancy might lead to the birth of infants who are small for their gestational age and have a low birth weight. But a recent study of 474 women, published in the Journal of Allergy and Clinical Immunology, did not find such a link. Below, Michael Schatz, MD, chief of the allergy department at Kaiser Permanente Medical Center in San Diego, and incoming president of the American Academy of Allergy and Immunology, discusses how this information can help pregnant women with asthma feel more comfortable with their decision to treat their lung condition.
How can pregnancy affect breathing in all women?
Interestingly, about 70 percent of women notice shortness of breath during pregnancy. Although one might expect that as the baby grows, in most of those women, it actually starts early in pregnancy. The exact causes aren't known, but it's felt to be related to extra breathing induced by hormones, presumably to provide the extra oxygen that the baby needs. As a result, the woman is breathing deeper during pregnancy and, for many women, it seems to translate into a feeling of shortness of breath. That can, of course, sometimes be confusing in people with asthma. But while any woman can experience shortness of breath during pregnancy, a cough, wheezing or chest tightness is associated with asthma.
Can pregnancy ever trigger asthma for the first time?
It does appear that some women develop asthma for the first time during pregnancy. In some of the women who appear to have asthma for the first time, if you go into some detail in the medical history, you find that they probably had some previous asthma, it just was very mild or very intermittent, so it wasn't noticed until now because the pregnancy seemed to make it worse.
Also, about a third of people with asthma may get worse during pregnancy and anywhere from a quarter to a third may find their asthma gets better during pregnancy. These changes that occur during pregnancy revert most of the time after delivery, or at least within the three months postpartum. So it does appear that it was really the pregnancy that did it.
How can untreated asthma put the baby or mother at risk?
The data suggest that women with asthma may have increased risks of the baby dying, either of a stillbirth or an early death, preeclampsia of the mother, low birth weight of the baby, or prematurity. It appears that it's the more severe and uncontrolled asthma that poses the greatest risk. There is also a risk to the mother of increasing the severity of asthma symptoms or episodes, and even of asthma death.
What medications are used to treat asthma?
The current classification of asthma basically divides patients into people with intermittent asthma and persistent asthma. In people with persistent asthma, the concept is that there are controllers, and rescue medicines. If adequate controller medicines are used, one would not need much rescue medicines. The inhaled steroids are the controller medicine of choice at all levels of persistent asthma during pregnancy and in general.
Intermittent asthma means you have symptoms less than twice a week, wake up in the night from asthma less than twice a month, and have normal pulmonary function tests when not on medicine. The person with truly intermittent asthma just needs the rescue medicines to treat their asthma when symptoms arise. So patients in that category don't need any preventative medicines.