The risk of giving birth to a premature or small infant is increased among women who have seizures while pregnant compared with the general population, researchers in Taiwan report.

Less than one percent of women have seizure disorder, known as epilepsy, note Dr. Herng-Ching Lin, from Taipei Medical University, and associates. Most of those women have no complications during pregnancy, but there is a higher rate of complications such as stillbirths and birth defects, and some antiepileptic medications have been tied to such complications.

Lin’s team wanted to figure out whether seizures, or simply having epilepsy, were risk factors for prematurity and other effects.

They used data from the Taiwan National Health Insurance Research Data set and analyzed records from 1016 women with epilepsy who gave birth between 2001 and 2003 and a group of 8128 women without epilepsy. A total of 503 (49.5%) women with epilepsy had seizures while pregnant.

Overall rates of low birth weight (less than 2500 grams) were 6.3% in the non-epilepsy group, 7.6% among women with epilepsy who did not have seizures during pregnancy, and 9.0% among those who had seizures.

Corresponding rates of premature birth - before 37 weeks - were 6.6%, 9.2% and 10.5%, and rates of small for gestational age (birth weight in the lowest 10 percent of the population) were 16.6%, 17.90%, and 22.3%.

Compared with controls, and after adjusting for sociodemographic factors, all three measures were significantly greater among those with seizures.

Among women with epilepsy who did not have seizures during pregnancy, only premature birth was significantly more likely compared with women without epilepsy.

“Similar patterns of risks remained, even when women with epilepsy who received antiepileptic drugs during pregnancy were included in the analysis,” Lin’s team notes.

The authors stress that seizure control during pregnancy should be a primary goal.

They conclude: “The obstetrician and neurologist should work together prior to conception and throughout the pregnancy to closely monitor seizures and contributing factors (eg, sleep deprivation and medication compliance).”

SOURCE: Archives of Neurology, August 2009.