When in Menstrual Cycle Does Headache Lead to Emergency Department Visit?

A significantly higher percentage of women presented to the emergency department (ED) for headache during the preovulatory interval of their menstrual cycle—when estrogen levels are on the rise and headaches are typically less frequent and severe—compared with other intervals of the cycle, according to an abstract presented at the American Academy of Neurology’s 73rd Annual Meeting, being held virtually April 17-22, 2021.

Findings may represent a delay in seeking care for perimenstrual attacks or could indicate other factors aside from hormone levels contributing to when women present for headache, authors wrote.

As females exhibit higher prevalence of migraine worldwide (18% vs 6% in males), and because the condition has been historically associated with menstruation, several studies have aimed to analyze estrogen’s role in migraine pathogenesis.

“Hormone levels can impact the severity and frequency of migraine and tension headaches,” authors wrote. They continued, “perimenstrual attacks, thought to be precipitated by falling estrogen levels, are more severe and refractory to treatment. Given this, we hypothesized that there is an increase in ED presentations for headache during the perimenstrual interval.”

Perimenstrual attacks are considered menstrual migraines if they occur within the 5-day window of the 2 days prior to menstruation and the first 3 days of menstruation.

To better understand the relationship between presentation to the ED for headache and intervals of the menstrual cycle in reproductive age women, researchers assessed all first time ED visits for the primary complaint of headache at a single health network.

All women between ages 18 and 42 with data regarding their last menstrual period (LMP) who presented to the Montefiore Health System network between January 2017 and December 2019 were included in the study.

Menstrual cycle phase was based on a 28-day cycle by calculating the time from the start of each woman’s LMP to ED visit, authors explained. “Using day 1 as the start of menstruation, menstrual intervals were defined as preovulatory (days 5-11), periovulatory (days 12-18), postovulatory (days 19-25), and perimenstrual (days 26-4),” they said.

A total of 4996 women with a mean (SD) age of 29.4 (7.1) and who presented to the Montefiore ED for the primary complaint of headache were included in the analysis. Approximately 7% of women were taking hormonal contraceptives at the time of presentation.

Researchers found:

• 1154 (23.1 %) were within the perimenstrual interval
• 1272 (25.5%) were preovulatory
• 1003 (20.1%) were periovulatory
• 653 (13.1%) were postovulatory

Overall “significantly more women presented during the preovulatory period compared to the perimenstrual (z=2.797, P=.005) and all other intervals,” researchers concluded.

Reference

Jicha C and Pavlovic J. Relationship between intervals of the menstrual cycle and presentation to the emergency department for headache. Presented at: American Academy of Neurology 73rd Annual Meeting; April 17-22, 2021; Virtual. Accessed April 19, 2021. https://index.mirasmart.com/AAN2021/PDFfiles/AAN2021-002935.html