Epilepsy and Pregnancy
Highlights: Plan the pregnancy. Discuss with the patient beforehand (Start before pregnancy and continue throughout) Do not stop/alter doses of anti-epileptic drugs unless absolutely essential. Remember, a seizure is more dangerous than the side effects of anti-epileptic drugs. There is only marginal increase in the risk of foetal malformation. Advise to avoid all addictions and bad habits (smoking, alcohol, drugs) Continue breastfeeding if possible. Consider vitamin K. Prenatal exposure of anti-epileptic drugs do not cause significant cognitive impairment.
Women of child bearing age who have epilepsy have many questions about how epilepsy and the anti-epileptic medications they are taking will affect them and their unborn child during pregnancy. Epilepsy does impose special risks for pregnancy and one should be aware of these risks. The risks, however, can usually be managed in such a way as to keep the mother healthy and give her a very good chance of delivering a normal healthy baby.
What are the special risks to pregnancy associated with epilepsy?
Risks to the mother: Pregnancy can increase the frequency of seizures in the mother. This is not a high risk. About half of pregnant women have no change in the number of seizures during pregnancy. For some, the frequency decreases. But for about one fourth of pregnant women, seizure frequency increases. Many women experience this increase in seizure frequency because they reduce the amount of antiepileptic medication they take.
Risks to the fetus: The mother’s seizures represent the single largest risk to the unborn because the fetus can be seriously deprived of oxygen during the mother’s seizure. The fetus may, of course, be injured if the mother falls, is involved in an auto accident, or seriously burns herself during a seizure. Thus the goal during pregnancy should be to prevent all seizures. Children born to women with epilepsy are, on average, smaller in size and weight when compared to children born to women who do not have epilepsy. The reasons for this discrepancy are not clear. The difference does not appear to be related to antiepileptic medications because it remains whether the mother took medication or not. The difference in birth weight is not large enough to worry about. There is a somewhat greater risk of fetal malformation when the mother has epilepsy. Some of these malformations include a small head, slowed growth, and impaired intellect. Certain other abnormalities, such as cleft lip, cleft palate, heart abnormalities, and spina bifida are seen more frequently in children born to mothers on antiepileptic medications. Less serious fetal abnormalities include crossed eyes, drooping eyelids, broad fingers, decreased muscle tone, hernias, and clubfeet. However the risk of fetal malformations associated with epilepsy is very small. The fetal risk of pregnancy in normal women is about 3%. In women with epilepsy, the risk is 5 % i.e. just 2% high. Other common diseases represent a much higher risk for fetal deformity than epilepsy e.g. diabetic women have 8% risk much higher compared to epilepsy. There is considerable controversy about the risk to the fetus of antiepileptic drugs. In general the risk from the drugs is very small. A seizure during pregnancy is much more dangerous to the development of the fetus than the dangers associated with anti-epileptic medications. Thus if the risk for recurrent seizures is high then medication must be used. The choice of drug clearly depends on the type of seizures (Classification of epilepsy). Prepare patient before she becomes pregnant.
Anti-epileptic medications can lower the effectiveness of oral contraceptives (OCP). If the patient is taking OCP, dose adjustment may be required or alternative or additional methods of contraception may be considered. Valproate is one drug that does not impair effectiveness of OCP. Newer antiepileptic drugs like Lamotrigine, Gabapentine, or Vigabatrine also do not appear to interact with OCP, but these are not used as monotherapy at present. There are several different types of epilepsy. Different drugs control certain types of epilepsy best and are less effective for other types. Therefore, it is important to determine the type of epilepsy accurately to treat with the lowest dose of the most effective drug. Seizures themselves present the greatest risk to the fetus, so their prevention is the most important measure to protect the baby. If a patient is taking more than one medication for epilepsy discuss with a specialist doctor, whether you can stop any of them prior to pregnancy. The possibility of delivering a baby having certain brain malformations, such as spina bifida, is slightly increased for women with epilepsy. This risk can be almost eliminated by taking 1 to 5 mg. of folic acid every day. These brain malformations occur very early during pregnancy, usually before a woman is even aware that she is pregnant. Therefore, to be effective, folic acid should be given to all women who may become pregnant. There are certain risk factors for fetal malformations that have nothing to do with epilepsy. Many of these risk factors can be easily eliminated. Among the most important are:
Smoking: There are no good reasons to smoke. If your patient smokes, take this opportunity to eliminate the habit. Alcohol : Fetal alcohol syndrome, caused by the consumption of alcohol by the mother, is a serious complication of pregnancy. It is best to refrain from all alcohol consumption during pregnancy, especially during the first three months. Illegal Drugs : All addictive drugs are harmful to the fetus. The most recent data are showing that permanent brain damage is caused by many of these drugs. Plan de-addiction before pregnancy, if possible.
All non-essential medications: No drug can be considered absolutely safe for a developing fetus. Eliminate as much medicines as possible. If you must give one of these drugs, check whether there is any special risk for pregnancy or epilepsy.
During Pregnancy:
Even though pre-pregnancy counselling is worthwhile, very often I see patients in whom pregnancy was not planned or worse even primary physician had no idea as how to handle such cases or when to refer them to specialist. Such pregnant patients need additional counselling on the value of good drug compliance, monthly neurological examination, drug monitoring (when required), individualized obstetrical care including ultrasound examination and determination of Alfa fetoprotein (AFP) etc. In case of Valproate or Carbamazepine exposure and a family history of neural tube defects, amniocentesis for AFP analysis and acetylcholinesterase electrophoresis should also be considered. It is very important that all of the doctors (primary physician, neurologist, obstetrician etc.) taking care of such patient are aware of the patient’s epileptic condition and that they are communicating with each other. Supplementation of Vit. K1 10mg/day should be initiated in late in third trimester to prevent neonatal haemorrhage. Trimethadione is absolutely contraindicated. Drugs and doses: In a women with active epilepsy the daily dose is titrated on clinical grounds e. g. seizure controls and adverse effects. Change in plasma concentration of drug should not necessarily prompt revision of the daily dose in asymptomatic patients. Unfortunately non-specialists often recommend reduction of daily doses or even complete withdrawal of medicines, when pregnancy is diagnosed in a women with epilepsy. This may lead to grave consequences including foetal loss or permanent damage to the brain of foetus. Avoiding seizures is the most important thing one can do to protect the baby. Taking the appropriate medication at the correct dose is the most effective thing one can do to prevent seizures.
During The Neonatal Period
The plasma concentration may increase following delivery and may be associated with clinical side effect. Sedation and withdrawal may occur in newborn. The signs of drug withdrawal may last several weeks but always disappear. Oral vitamins K with 2 mg at birth, at the end of first week, and at the fourth week are recommended for prevention of late haemorrhage in the newborn. Sleep deprivation should be minimised e. g. family members may take care of the baby during night. Breast-feeding should be encouraged because of the general health and psychological benefit for the mother and the child. If sedation occur the amount of breastmilk delivered can be reduced. If sedation does not improve then breastfeeding can be discontinued. There is no reliable data to suggest that prenatal exposure to antiepileptic drugs cause cognitive impairment in activities of daily life. Finally the infant requires regular follow up. Prevention of seizure related accidents of the child should be part of the counselling.
