Epilepsy does affect pregnancy, but most women with epilepsy have healthy pregnancies and deliver healthy babies. The main concerns center on how pregnancy changes seizure patterns, the effects of anti-seizure medications on fetal development, and the physical demands of the postpartum period. With planning, these risks can be substantially reduced.
How Pregnancy Changes Seizure Frequency
For the majority of women, seizure frequency stays about the same during pregnancy. In a large study tracking over 1,100 pregnancies, 58% of women had no change in seizure frequency compared to the nine months before conception, and nearly two-thirds of that group remained completely seizure-free throughout. About 26% experienced more frequent seizures, while 11% actually improved.
Looking at changes within pregnancy itself, about 21% of women had increased seizure frequency in the second and third trimesters compared to the first, while 65% stayed stable. So the odds are in your favor that pregnancy won’t dramatically worsen your seizures, though roughly one in four women does see some deterioration.
Why Hormones Shift Seizure Thresholds
The two main reproductive hormones pull in opposite directions when it comes to seizures. Estrogen generally makes brain cells more excitable and lowers the seizure threshold. Progesterone does the opposite: it produces a metabolite that boosts the brain’s main calming chemical (GABA), acting as a natural anticonvulsant.
During pregnancy, both hormones rise dramatically, but the balance tips in a somewhat protective direction. The form of estrogen that dominates in pregnancy (estriol) may not be as seizure-promoting as the form present outside of pregnancy (estradiol). Meanwhile, progesterone climbs steadily throughout all three trimesters. This hormonal environment helps explain why most women don’t see their seizures worsen, though the overall picture is complex enough that outcomes vary widely from person to person.
Why Medication Choice Matters Before Conception
The biggest modifiable risk in epilepsy and pregnancy is medication. Not all anti-seizure drugs carry the same risk to a developing baby, and the differences are stark. Valproate (sometimes sold as Depakote or Epilim) poses the highest known risk: the rate of major birth defects ranges from about 6.7% to 10.3% across large international registries. By comparison, lamotrigine carries a risk of roughly 2.1% to 2.9%, and levetiracetam sits around 2.0% to 2.8%. These lower-risk medications are now widely preferred for women of childbearing age.
Switching medications takes time. Your body needs weeks or months to adjust, and the goal is stable seizure control on the safest possible drug before you conceive. This is why preconception planning is so important. If you’re on valproate and considering pregnancy, the conversation about alternatives should happen well in advance.
Folic Acid at a Higher Dose
All pregnant women are advised to take folic acid to reduce the risk of neural tube defects like spina bifida. If you take anti-seizure medication, you need a higher dose: 5 mg daily, which is roughly ten times the standard recommendation. This higher dose requires a prescription because over-the-counter supplements don’t come in that strength. Ideally, you start taking it before conception, since the neural tube forms in the earliest weeks of pregnancy, often before you know you’re pregnant.
Monitoring Medication Levels During Pregnancy
Pregnancy changes the way your body processes medications. Blood volume increases, kidney filtration speeds up, and liver metabolism shifts. The result is that drug levels in your blood can drop even though you’re taking the same dose, potentially leaving you under-protected against seizures. Doctors typically check your blood levels of anti-seizure medication regularly throughout pregnancy, often every four weeks, and may increase your dose by 30% to 50% to compensate.
Interestingly, one study found that the exact frequency and timing of these blood level checks didn’t clearly predict whether women had breakthrough seizures. This doesn’t mean monitoring is useless, but it suggests that seizure control during pregnancy involves more than just hitting a target number on a lab test. Factors like sleep, stress, and the hormonal shifts described above all play a role.
Seizures During Labor and Delivery
The risk of having a seizure during labor itself is low. Across studies, about 1% to 2% of women with epilepsy experience a generalized tonic-clonic seizure during labor or delivery. The risk is higher for women with certain types of generalized epilepsy (up to 12.5% in one small study) and essentially zero for women with partial (focal) epilepsy in that same research.
One important finding: none of the women who had adequate medication levels in their blood before labor had seizures, compared to about 8% of those with levels that had fallen too low. This reinforces how important it is to keep up with your medication throughout late pregnancy and into labor. Your medical team will typically ensure you continue taking your medication on schedule during delivery.
Vitamin K in the Final Weeks
Some anti-seizure medications, particularly older ones like phenobarbital, carbamazepine, and phenytoin, interfere with vitamin K metabolism. Vitamin K is essential for blood clotting, and newborns already have very low levels at birth. Babies born to mothers on these medications face a higher risk of bleeding complications. To counter this, daily vitamin K supplementation (10 mg) is typically recommended starting at 36 weeks of pregnancy for women taking enzyme-inducing anti-seizure drugs.
The Postpartum Period
The weeks after delivery are a vulnerable time. Sleep deprivation is one of the most reliable seizure triggers, and newborn care virtually guarantees disrupted sleep. For women with genetically based epilepsy, this trigger is especially potent. The practical solution is straightforward but requires planning: arrange for family members or a partner to handle some nighttime feedings so you can get longer stretches of unbroken sleep. If you’re breastfeeding, pumping milk for overnight bottles is one way to make this work.
Medication levels also need attention postpartum. If your dose was increased during pregnancy to compensate for faster metabolism, those increases may need to be tapered back down after delivery as your body returns to its pre-pregnancy state. Without adjustment, you could end up on a higher dose than you need, with more side effects.
Breastfeeding on Anti-Seizure Medication
Most anti-seizure medications are compatible with breastfeeding, though the details depend on the specific drug. Levetiracetam, one of the most commonly prescribed options, does pass into breast milk and can occasionally cause drowsiness in infants, particularly at higher doses or when combined with other medications. In one study of 20 mothers on levetiracetam, three reported drowsiness in their breastfed babies, all at doses of 1,500 mg daily or higher. One newborn on a combination of medications required hospitalization for sedation and poor feeding, but recovered fully after breastfeeding was stopped.
The general approach is that being on anti-seizure medication is not a reason to avoid breastfeeding, but you should watch for signs of unusual sleepiness, poor feeding, or slow weight gain in your baby, especially in the first few weeks when the infant’s ability to process these drugs is still developing.
Will Your Child Inherit Epilepsy?
Most children born to a parent with epilepsy do not develop epilepsy themselves, but the risk is somewhat elevated compared to the general population. If the mother has epilepsy, the child’s risk falls between about 3% and 9%. If the father has epilepsy, the risk is lower, roughly 1% to 4%. The general population risk of developing epilepsy over a lifetime is about 1% to 2%, so having a parent with epilepsy raises the odds modestly but not dramatically. The degree of genetic risk depends heavily on the type of epilepsy. Some forms have a stronger hereditary component than others, which is something a genetic counselor can help clarify for your specific situation.