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Pregnancy & asthma

Asthma attack- what to do | Medications | Monitoring | Labour & delivery | After the baby is born

Pregnant women are breathing for two. When asthma is controlled, women with asthma have no more complications during pregnancy and giving birth than women who don't have asthma. However, uncontrolled asthma during pregnancy can lead to serious maternal and fetal complications. If you have asthma and you're pregnant, or planning to become pregnant, see your doctor.

Good asthma control is very important

When you're pregnant, it's especially important to have your asthma under good control: breathing difficulties in the mother can limit the oxygen supply to the fetus.

Your asthma well-controlled if you are:

  • Active without experiencing any asthma symptoms
  • Sleeping through the night, and not waking due to asthma symptoms
  • Attaining your personal best peak flow number. This is an important indicator as it is an objective assessment measure.
How asthma changes when you're pregnant

In general, one third of pregnant women with asthma notice that their asthma symptoms improve during pregnancy; one third of women have asthma symptoms that stay the same, and one third of women have asthma symptoms that get worse.

Risks of badly controlled asthma when you're pregnant

If a mother has uncontrolled asthma, there is a higher risk for:

  • Premature birth
  • Low birth weight
  • Maternal blood pressure changes (i.e. pre-eclampsia)
Preventing asthma while you're pregnant

Acute asthma episodes endanger the fetus by reducing the oxygen it receives. It is therefore important to prevent a asthma episode during pregnancy and labour and delivery.

Some ways to prevent asthma episodes:

  • Control your environment: avoid your asthma triggers and inducers. Avoiding triggers should be the first form of asthma therapy during pregnancy.
  • Continue taking your regular asthma medications (as precribed by your doctor) during pregnancy and labour and delivery.
  • Get your flu shot. The flu shot can be taken after the first 3 months of pregnancy. This shot is recommended for almost everyone, and especially people with asthma. It is not recommended for people with an egg allergy.
  • Exercise carefully, under doctor's supervision. Many people's asthma symptoms are triggered by exercise. Pregnant women with asthma should exercise, under the supervision of their physician. You can prevent or reduce exercise-induced asthma by following these steps.
  • Don't smoke. A pregnant woman who smokes runs a greatly increased risk of having a severe asthma episode at some time in the pregnancy. This could seriously reduce the oxygen supply to the fetus, especially if the blood of the fetus already contains a large amount of carbon monoxide gas from cigarette smoke. Infants are 3 times more likely to die of Sudden Infant Death Syndrome (SIDS) if their mothers smoked during or after pregnancy. Learn more about smoking and pregnancy.
  • Avoid second-hand smoke. Both you and yourbaby can be hurt by second-hand smoke. Ask friends and family not to smoke near you or in your home or car.
Asthma medications and pregnancy

Most asthma medications are safe during pregnancy. The risks of uncontrolled asthma are far greater than the risks to the mother or fetus from the medications used to control asthma. If you are pregnant of plan to become pregnant, tell your doctor. Your doctor may change your medications, depending on what you are taking.

Asthma care should be integrated with obstetric care. The same health care provider if possible should be used for both. A team approach should be used if more than one doctor is involved.

Medications to avoid during pregnancy

Take your asthma medications as directed by your doctor, but be careful about taking any other medications. There are many over-the counter, prescription, and herbal medications that should not be taken during pregnancy. Check with your doctor or pharmacist before you take any over-the-counter, prescription, or herbal medicine if you are pregnant.

Here are some medications you should avoid during pregnancy. This is not the complete list of things you should avoid:

  • Iodides : can cause goiter in the newborn
  • Tetracycline : can cause permanent staining of the childs teeth.
  • Aspirin or ASA products : can cause severe life-threatening asthma episodes during pregnancy if the expectant mother is sensitive to this drug.
  • Sulfonamides : in late pregnancy are associated with increased bilirubin in the newborn's blood.

The above is NOT the complete list of medications you should avoid during pregnancy. If you have any questions about prescription or over-the-counter medications during pregnancy, please speak with your doctor or pharmacist. You can also learn more about healthy pregnancy and medications from Motherisk, a free, evidence-based pregnancy and drug information service based at the Hospital for Sick Children in Toronto.

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Monitoring your level of asthma control

Your doctor will want to take objective assessment measures to know how your breathing is. There are many body changes associated with pregnancy; some changes are due to asthma. Objective measures are essential for assessing and monitoring asthma in order to make appropriate medication changes.

The doctor can monitor your asthma by using:

  • Spirometry (a simple breathing test that measures how much air you can push out of your lungs, and how fast)
  • A peak flow meter, a hand held device to measure the rate you can blow air out of your lungs

The goal is to try and maintain normal, or near normal pulmonary function rates.

The doctor will asses the health of the fetus by:

  • Ultrasound : to provide early indication of foetal growth. A gel is put on the abdomen, and a hand-held sensor provides an image of the fetus which is projected onto a computer screen.
  • Electronic fetal heart rate monitoring : a Doppler is used to hear the fetal heart rate through the mothers abdomen.
  • Nonstress test : can be used to assure fetal well-being. These tests monitor the fetal heart rate over a period of time.
  • Daily kick charts : these are used to monitor fetal activity. The mother keeps a record of when she feels the fetus kick or move. The charts can be compared over a period of time to see the fetus activity pattern.
Managing an asthma attack

If you are having an asthma attack

  • Stop all activity
  • Take your rescue medicine (blue puffer) right away, as directed by your doctor.
  • Sit down
  • Call 911 right away if:
    • The rescue medication (blue puffer) does not help right away
    • The rescue medication wears off and your symptoms return
    • Your symptoms keep getting worse
    • Your symptoms are worse than usual
    • You notice the baby is moving around less
    • You feel worried

If your breathing does not improve, you can keep taking your rescue medicine (blue puffer) until the ambulance arrives.

Prevent asthma attacks by:

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Asthma during labour & delivery

Your due date is near. You have packed your bag for the hospital.

What can you expect when you go into labour and delivery?

You can expect:

Monitoring during labour and delivery

The mother and fetus are monitored during labour and delivery to ensure the good health of both. This is especially necessary for women with asthma.

Fetus: As in most labours, the fetus is monitored electronically on admission to hospital. If the mother's asthma is under control and in low-risk patients, continuous monitoring may not be necessary. During the course of labour, continuous fetal monitoring may be considered.

Mother : You will have a peak flow rate taken on admission to labour and delivery unit, and every 12 hours following. If asthma symptoms develop, peak flow rates should be measured after treatments. An I.V. may be necessary to ensure you are well hydrated. Adequate analgesia (painkillers) will limit the risk of asthma symptoms.

Medications during labour and delivery

The mother's regularly scheduled asthma medications should be continued during labour and delivery.

For the women whose asthma improved during pregnancy, and their medications appropriately reduced, an increased need for medication may occur immediately following delivery.

If your asthma has not been under good control, your doctor may give you specific instructions to go to the hospital earlier in the labour.

You should not hesitate to ask for a pain killer. This will help limit your risk of asthma symptoms (bronchospasm).

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Asthma after the baby is born (post-natal period)

Your beautiful new addition to your family has arrived. What can you expect next?

  • After the baby is born, it may be necessary to change your asthma medications and doses. Because some women experience changes in their asthma during pregnancy, the asthma may again change following delivery.
  • The postpartum period can involve anxiety surrounding the newborn, fatigue, and possibly significant postpartum depression. For this reason, you and your dotor should monitor your asthma very closely to make sure it stays well-controlled.
  • Breastfeeding
  • Inhaled bronchodilators and inhaled anti-inflammatories do not appear to cause side effects.
  • Theophylline gets into breast milk and can make the baby irritable.
  • Antihistimines should be avoided because they can cause sleeplessness and irritability in children. They can also reduce or prevent production of breast milk.
  • Avoid smoke. Infants are twice as likely to die of SIDS if their mother starts smoking again after giving birth

To keep your baby healthy, don't smoke, and don't let anyone smoke around your child or in your home. Children of parents who smoke have a much higher rate of colds and other upper respiratory infections compared to children whose parents do not smoke.

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