Researchers found pregnant women with epilepsy are at greater risk of maternal death and delivery complications than those without the disorder.
Epilepsy is brain disorder characterized by abnormal nerve cell activity that causes seizures. It is estimated that around 3 million adults and children in the US have the condition, with around 150,000 new cases diagnosed each year.
According to the study researchers, including Sarah MacDonald of the Harvard T.H. Chan School of Public Health in Boston, MA, around 0.3-0.5% of all pregnancies occur among women with epilepsy.
While it is understood that epilepsy can raise the risk of pregnancy- and delivery-related complications, such as fetal injury and preterm birth, MacDonald and colleagues note that there is inadequate data quantifying these risks.
"With approximately half a million women with epilepsy of reproductive age in the US, and 25,000 offspring born to these women annually, there is considerable need to understand the risks of pregnancy in this population," they note.
The researchers set out to address this data gap, analyzing the hospital records of almost 4.2 million women in the US who gave birth between 2007 and 2011. Of these women, 14,151 had epilepsy.
Applying these figures nationwide, the researchers say their study represents 69,385 women with epilepsy and 20,449,532 women without the condition.
Incidence of delivery complications was recorded, including Cesarean delivery, preterm birth, preeclampsia, stillbirth and maternal death, and length of hospital stay was also assessed.
10-fold greater risk of maternal death for women with epilepsy
The researchers found that the rate of maternal death was much higher among women with epilepsy than those without.
There was a rate of 6 deaths per 100,000 pregnancies among women without the brain disorder, while there were 80 deaths per 100,000 pregnancies for women with epilepsy - representing more than a 10-fold greater risk of maternal death.
In addition, the team found women with epilepsy were at greater risk of other complications, including preterm labor, preeclampsia and stillbirth. These women were also more likely to need Cesarean delivery and have longer hospital stays than those without epilepsy.
While the researchers are unsure exactly why women with epilepsy are at higher risk of delivery complications and maternal death, they say their findings are of concern:
"Regardless of the specific cause, the point that women recorded as having epilepsy have an increased risk of mortality remains a clinically relevant message suggesting that increased attention should be paid.
The disproportionate burden of maternal morbidity and mortality among women with epilepsy suggests that these are high-risk patients who may best be cared for in medical centers with subspecialty expertise in neurology, maternal-fetal medicine and critical care."
They add that further research is needed to determine the mechanisms underlying their findings and to identify interventions that might improve pregnancy outcomes for women with epilepsy.
In an editorial linked to the study, Dr. Jacqueline A. French, of the NYU Langone School of Medicine in New York, NY, and Dr. Kimford Meador, of the Stanford University School of Medicine, CA, say the findings from MacDonald and colleagues "provide important new information" about pregnancy risks for women with epilepsy.
They note, however, that the study raises more questions than it provides answers. "Most WWE [women with epilepsy] have uncomplicated pregnancies," they add. "We need to understand the mechanisms underlying these risks, including death, so that we can identify the specific population at risk and devise interventions to reduce these risks. Future studies need to confirm and build on the present findings to improve the care of WWE during pregnancy."
In January, a study published in the journal Neurology claimed people with epilepsy who sleep on their stomach may be at greater risk of sudden unexpected death than those who sleep in other positions.