Apart from possible adverse effects of medications, can acute asthma by itself be dangerous for the fetus?
Yes it can. Acute asthma causes lack of oxygen in the mother’s blood, and thus the fetus also suffers from lack of oxygen, sometimes more than the mother. While the fetus can tolerate this lack for some time, the same kinds of damage can be done that a lack of oxygen can produce during delivery: varying degrees of brain damage.
Did most of the asthmatic women you looked at tend not to take their maintenance medication during their pregnancy, at least at the beginning?
In our experience in Finland, if women are not specifically encouraged to do so by their doctors, they are overcautious, especially at the beginning, and tend not to take appropriate asthma medication. Unfortunately, many women are in fact discouraged from taking medication by doctors and nurses – who also tend to be overcautious. These are the same people who would never tell a diabetic patient not to take their medication during the first three months of pregnancy, yet this is often the instruction given to an asthmatic woman. It is not as though asthma can go untreated without consequences, just as in diabetes. Not taking antiinflammatory drugs greatly increases the risk of acute asthma.
Are there any typically-prescribed asthma drugs that should definitely not be taken during pregnancy?
No. If possible, inhaled drugs should be preferred during the first three months but it is very important to keep the asthma well controlled, even if this means taking oral prednisone.
Do you know what accounts for the higher rate of pre-eclampsia in the asthmatic women?
Not really. We do know that the more severe the asthma, the greater the risk of pre-eclampsia, but we don’t know whether it is the asthma or the drugs that cause this effect. Well-controlled asthma does not generally result in pre-eclampsia. However, it should be noted that the overall difference in risk for pre-eclampsia in asthmatic vs. non-asthmatic women, while statistically significant, is still quite modest. Also, pre-eclampsia can be very effectively treated.
What are the possible risks connected with asthma that account for the high incidence of elective caesarian sections in asthmatic women?
The only real risk is having acute asthma, or very severe symptoms, during delivery. We have seen this only rarely – three or four times in all of the approximately 700 women we have followed to date. Caesarian sections are done only if the asthma has been left totally uncontrolled in the weeks before delivery – if the mother has not been taking her medication. But obstetricians are generally very aware of this possibility, and can evaluate a patient very well. Obviously, acute asthma during labour should be avoided at all costs.
Does labour aggravate asthma, especially if you have exercise-induced asthma?
No. However, if symptoms do occur during delivery, using a bronchodilator for relief is always an option. But very few women end up requiring even this. Again, this happens only very rarely if asthma is well controlled.