St. Luke’s Maternal Fetal Medicine

Seizure Disorders

The effect of a seizure disorder in pregnancy is highly variable: seizure frequency may increase in as many as 50% of patients yet remain unchanged in the rest. If there is an increase in seizures during the first trimester of pregnancy, this may be due to adjustment of anti-seizure medication. Due to metabolic changes in the early parts of pregnancy, medication often needs to be increased. However, for all intents and purposes, the seizure disorder and its medications are treated the same during pregnancy.In the past, when multiple medications were used to treat seizure disorders during pregnancy, there was an association with “phenyl hydantoin syndrome.” This syndrome, which affects the fetus, may have been due to multiple medications being used during the pregnancy. State-of-the-art seizure therapy is now available, and today, phenyl hydantoin syndrome is rarely seen with proper medication levels. When using a single medication for seizure disorder, valproic acid is associated with an increased likelihood of neural tube defects (such as spina bifida), though less than 5%. The use of valproic acid during pregnancy requires regular medical supervision, including targeted ultrasound, as well as counseling regarding the drug’s affect on the fetus.

St. Luke’s Maternal Fetal Medicine
333 N. 1st Street, Suite 150
Boise, ID 83702
(208) 381-3088