Can the risk of malformations in epilepsy be reduced or eliminated by stopping anticonvulsant medication?
In theory, yes. However, this should never be attempted without full involvement of the specialist. Arbitrary cessation of anticonvulsant medication could have dangerous consequences. If, on careful assessment, a specialist feels that it is safe to attempt to come off medication for a woman planning to conceive, this may be done. However, this is only ever attempted in a case where there has been no seizure for a period of two years, preferably longer. More often than not, specialists advise continuing with medication but the preparation may be changed to a relatively safer one (for pregnancy). A planned pregnancy also allows for starting Folic acid supplements in the pre-conception phase, ideally about three months before actively starting to try for a baby.
Does medication add to the risk of malformation?
The answer to this is, broadly, yes. However, there is a wide variety of anticonvulsant medication and new ones are coming on the market all the time.
Of the traditional anticonvulsants, carbamazepine (Tegretol®, Carbagen®SR) is considered to be the safest, in relative terms. It is, however, not completely free of side-effects to the fetus, and may occasionally cause defects, mostly minor. Phenytoin (Epanutin®) may cause some defects of the skull bones, digits and occasionally may have long-term consequences including mental retardation, with learning difficulties. It should be emphasized here that all these are quite uncommon.
Should anticonvulsant medication be stopped if I am planning to conceive or discover I'm pregnant?
The issue of continuing with medication during pregnancy is rather complex.
For the majority of women with epilepsy, continuing with medication is not only desirable but imperative. In carefully selected cases, where there have been no seizures for at least two years, an attempt to stop anticonvulsants in the preconception period could be made. If she remains free of seizures, she could be treated by observation alone. Unfortunately, 30 per cent of all patients who try this strategy have a recurrence of seizures and have to go back on medication.
It is considered unwise to adopt this strategy if you are already pregnant. In this case, medication should be continued.
What about other types of anticonvulsants in pregnancy?
A few patients may be maintained on Valproic acid (Epilim®)and Trimethadione (Tridione®). These are not commonly used. If a patient is on one of these, it may be changed to a safer variety such as carbamazepine or Lamotrigine. Both Trimethadione and Valproic acid have been associated with a variety of birth-defects and Valproic acid is notorious for causing spina bifida and other defects of the spinal column. valproic acid is also known as Sodium valproate.
The decision to change medication is not always automatic or straightforward since you may have tried the apparently safer alternatives in the past with disappointing results. Alternatively, you may have a history of seizures that are very difficult to control and your doctor may judge it unsafe to take the gamble.
Lamotrigine (Lamictal®). This anti-epileptic taken on its own in pregnancy is considered to be relatively low risk compared to other anti-epileptic medications. The risk is significantly when taken in combination with such drugs as Valproic acid (Epilim®) as is the case sometimes.
Vigabatrin (Sabril®) has also been associated with birth defects and the standard advice is to avoid in pregnancy unless the benefits are deemed to outweigh risks.
As a rule, anybody taking any of the anti-epileptic drugs should not stop without consulting her doctor first.
Does an epileptic mother need to take any other precautions during the course of the pregnancy?
Anticonvulsant (anti-epileptic) medication makes the epileptic mother vulnerable to developing a folic acid deficiency. Folic acid will be recommended as a supplement, preferably staring before conception and continuing throughout the course of pregnancy.
Also, there is a small risk of bleeding (for the baby) and doctors will advice taking Vitamin K1 (Konakion®) supplements towards the end of pregnancy to prevent this.
Hereditary effects of epilepsy
If the father of the baby is an epileptic, does that still carry an increased risk of malformations for the fetus?