Asthma is an immunologic condition where certain irritants, or unknown causes, result in increased secretions and bronchospasm, which interfere with air movement. In severe cases, there can be something called hypoxia, or low oxygen, and hypercapnia, a build up of carbon dioxide, in the body. "Status asthmaticus," the most severe expression of asthma, can even result in death.
Asthma can be a serious real health concern, especially when mixed with pregnancy. The American Academy of Allergy, Asthma, and Immunology (AAAAI) says that with proper medical supervision asthma in pregnancy is manageable. But if not treated, "there is a direct relationship between lower birth weight and uncontrolled asthma."
In pregnancy, half of all asthma patients experience no change in the course of their disease. Another fourth even may notice an improvement in their asthma symptoms, while another fourth complain of worsening asthma.
For most women, asthma management during pregnancy won't require change, because what worked to keep breathing smooth prior to pregnancy will continue to work just a well during pregnancy. But because pregnancy itself is a challenge to many women's physiologic state, when things go bad (as in a bad asthmatic attack), things can go very bad. Therefore some obstetricians may be more aggressive in prescribing antibiotics to pregnant asthma patients who present with an otherwise uncomplicated upper-respiratory infection.
Treatment for asthma, besides eliminating the typical allergens of pets, cigarette smoke, household dust, and environmental allergens (pollen, etc.), is based on adrenaline-like substances that can help dilate the bronchial tree. Brethine, one particular agent, is also used to stop uterine contractions in preterm labor. Hydrocortisone and methylprednisolone, both steroids, can be used in severe asthma cases. And aminophylline, the mainstay of chronic management, can be used safely under the direction of an obstetrician.
One of the biggest risks of asthma in pregnancy is when some other respiratory problem is thrown into the mix, such as pneumonia. You can only add so many problems to someone's breathing before things become very dangerous. Less oxygen for the mother means less oxygen for the baby. And for this reason, many obstetricians would rather nip a new, developing problem in the bud than wait for it to become so unmanageable that it could threaten both mother and unborn baby.
Women with asthma can anticipate a full reproductive life. With few exceptions, asthmatic pregnancies can be managed without undue intervention.