A new study offers the first guidelines indicating when a headache in a pregnant woman could be a sign of concern and require medical attention as it may signal pregnancy complications.
For example, if a pregnant woman with high blood pressure and no history of headache suddenly develops a headache that quickly gets worse, she could be at risk for pregnancy complications, including preeclampsia, which put both the mother and fetus at risk.
The new study was conducted by researchers at Montefiore Health System and Albert Einstein College of Medicine at Yeshiva University.
“Headaches during pregnancy are quite common, but it is not always easy to distinguish between a recurring, preexisting migraine condition and a headache caused by a pregnancy complication,” said lead author Matthew S. Robbins, M.D., director of inpatient services at Montefiore Headache Center, chief of neurology at Jack D. Weiler Hospital of Montefiore, and associate professor of clinical neurology at Einstein.
“Our study suggests that physicians should pay close attention when a pregnant woman presents with a severe headache, especially if she has elevated blood pressure or lack of past headache history. Those patients should be referred immediately for neuroimaging and monitoring for preeclampsia.”
Symptoms of preeclampsia (previously called toxemia), which may be related to an abnormal interaction of blood vessels that supply the placenta, can include high blood pressure, headaches, blurry vision, or abdominal pain. Some patients, however, have no symptoms.
Preeclampsia typically occurs during the second or third trimester of pregnancy. Depending on the severity and the age of the fetus, treatment ranges from bed rest for mild preeclampsia to premature delivery if the condition is severe.
For the study, the researchers looked at the records of every pregnant woman with a headache who had been referred for a neurological consultation at Weiler Hospital over a five-year period.
This involved a total of 140 women with an average age of 29. A large majority of the patients were Hispanic or African-American, reflecting the makeup of the Bronx population.
Most (91) of the patients had primary headaches, 90 percent of which were migraines. Among the 49 patients with a secondary headaches, 51 percent were diagnosed with pregnancy-related high blood pressure, including the 38 percent of women who had preeclampsia.
The most pressing sign of a secondary headache among pregnant women proved to be high blood pressure. Compared to pregnant women with a headache but no high blood pressure, women with a headache plus high blood pressure faced a 17-fold increased likelihood that their headaches were caused by some other condition.
“In most of these patients, their elevated blood pressure was driven by preeclampsia,” said Robbins.
The researchers found that another red flag for a headache that could indicate trouble was lack of a previous history of headaches, which was linked to a five-fold increased likelihood that the headache was secondary to something else.
Other warning signs were fever, seizures, and headaches in the absence of phonophobia (sound sensitivity) and psychiatric problems.
The study is published online in the journal Neurology.