SEIZURES DURING PREGNANCY
What is a seizure?
A seizure is a change in behaviour, or a muscle spasm or contraction.
Why do seizures happen?
The nerve cells in the brain produce electrical signals that send messages throughout the body. These messages control the body's movements and functions. In a person with a seizure disorder the normal pattern of these messages is disrupted, and seizures result.
What effect do hormones have on seizures?
Hormones can have a significant effect on seizure disorders. In women, the hormones that can have an effect include the sex hormones that control the reproductive system: estrogen and progesterone. Changes in the levels of these hormones can make seizures more or less likely. Some women notice changes in their seizure pattern when hormone levels change, as they do during pregnancy or just after it.
How might my pregnancy change my seizures?
Pregnancy can change both the pattern of seizures and the way the body responds to anti-epileptic medication. For that reason you should consult your obstetrician–gynecologist and your neurologist, who will help you find the best way of controlling your seizures without risking harm to the baby from medication. The dose, or the number of medicines taken, may need to change during pregnancy. These changes may be necessary because of hormonal changes and changes in the way the body processes medication during pregnancy. Blood tests may also be done throughout the pregnancy to confirm that drug levels remain stable. If the levels are too high, side effects can occur. If they are too low, seizures can occur.
If I have a seizure disorder, how can I prepare for a pregnancy?
You should arrange to see your doctor before you become pregnant to discuss your care. If you have had no seizures for 2 years or more, it may be possible to withdraw your medication gradually. If your doctor does not recommend reducing the dose or stopping the medicine, you may need to be prescribed a different one. Some medicines are more harmful to the baby than others, so you may need to change medication during pregnancy. You should know that seizures are more harmful to a woman and her baby than any medicine. So if you are still having seizures, it is important to prevent them with some form of medication. Anti-epileptic drugs affect the way the body uses folic acid. Not having enough folic acid has been linked to problems during pregnancy and to certain birth defects. Taking folic acid before and during the first weeks of pregnancy can reduce the risk of these problems.
What is the chance that women with seizures will have a baby with birth defects?
For women with a seizure disorder, the risk of having a baby with birth defects is 6–8%, slightly higher than for women without a seizure disorder (2–3%). This risk may be related to the disorder itself or to the medication used to treat it. The types of defect, along with other problems they may cause, include the following:
- Cleft lip or palate (the lip or the roof of the mouth is not completely closed)
- Heart defects
- Neural tube defects (such as spina bifida)
- Low birth weight (a small baby)
- A small head
- Developmental delay
- Intellectual disability
- Bleeding (clotting) problems.
The children of women with a seizure disorder are also at increased risk of developing a seizure disorder themselves.
Will my baby need special care after birth?
Anti-epileptic drugs lower the natural levels of vitamin K (the vitamin that helps blood to clot) in the body. Immediately after the birth your baby will be given an injection of vitamin K to prevent problems caused by low levels of this vitamin. Most women with a seizure disorder can breastfeed their babies, because anti-epileptic drugs are present in small amounts in breast milk and in most cases are not enough to affect the baby.
Will my medication change after the birth?
After the birth your medication may need to be adjusted again. You may also want to choose a method of contraception. Many anti-epileptic drugs change the hormone levels in a woman's body, and these hormonal changes can reduce the effectiveness of hormonal methods of birth control. You may need to change your method of contraception. Some women choose to use a barrier method (a diaphragm, spermicide or condoms) together with a hormonal method.