If you get migraines, you're not alone. The Migraine Research Foundation estimates that 18% of adult women in the U.S. have migraines. Migraine is also heavily affected by sex; three times as many women as men experience migraines of some kind, according to NPR, and researchers believe the difference is partially explained by hormones. For women with migraine, that means that choosing a hormonal birth control can be a fraught experience. Various kinds of birth control can have consequences for migraine-prone women, including increased migraine frequency and higher likelihood of other conditions, experts say.
When it comes to migraines, all birth control options are not created equal. Hormonal birth control options include the combined pill, the mini-pill, hormonal IUDs, implants, or the Depo-Provera shot. Each will have different impacts on people who get migraines depending on the proportion of hormones used and the types of migraines people experience. (Non-hormonal birth control options like condoms won't have an impact on migraines, through the copper IUD can increase bleeding, which is associated with higher migraine symptoms.)
"Migraines are awful," family physician Dr. Julie Graves, Associate Director of Clinical Services at Nurx, tells Bustle. "Besides the terrible pain, there is often nausea, vomiting, and difficulty tolerating light or sound. Women who have migraines may find that taking a birth control pill, especially a low-estrogen pill on a continued basis (having only one to three periods a year) reduces the frequency and severity of migraine, while other women have their migraines worsened by combination birth control pills with estrogen." Each person's reaction to contraception is very individual, which means finding the right contraceptive choice can be a process of trial and error.
The combined pill is commonly sold as a packet of 21 active pills and seven sugar or placebo pills, or 24 active and four placebo. The active pills contain hormones that prevent ovulation, while the placebo pills allow for a withdrawal bleed that mimics a period. However, that withdrawal week isn't necessarily good news for women with migraines. "The migraines associated with oral contraceptives occur most often during the placebo week when the pills don't contain any estrogen," Harvard Health wrote. The change in hormone levels triggered by the inactive pills can bring on migraine symptoms, which means that women with migraines on the combined pill are often recommended to skip these withdrawal weeks entirely.
However, for women who experience migraines with auras — where headaches appear at the same time or after sensory experiences like flashing lights, tingling or blind spots in the visual field — combined pills aren't recommended at all. “If you suffer from migraine with aura you should not take the combined oral contraceptive Pill," a spokesperson for the Migraine Trust tells Bustle. "This is because the combined pill is associated with a very small increased risk of ischaemic stroke." Ischaemic strokes occur when blood clots block blood flow to the brain.
The reason for this is the hormone estrogen, which is present in the combined pill in the form of ethinyl estradiol. According to a review of 15 different studies published in 2017, the higher the levels of estrogen in a combined pill, the more likely it is to cause stroke in women prone to aura migraines. “Statistics show that the risk is extremely small but nevertheless it is still a risk, which can be avoided," says the Migraine Trust. Research indicates that the combined pill only affects women with migraine in this way if they experience auras, too; women with what's known as "common migraine," or non-aura migraine, don't have an increased stroke risk. As yet, research doesn't explain why this is.
This problem may be less common now because of how birth control has evolved. In older combined pills, the study explained, high doses of estrogen were used, while these days the dose is up to 80% lower. The risk of stroke for people who get migraines with aura is far lower for these estrogen-light pills, though it does still occur. If you experience auras with migraines, says the Migraine Trust, estrogen-free birth control is the way forward. "The risk from the Pill is due to ethinyl estradiol, and not progestogen. So progestogen-only contraceptives are a safer alternative," the Migraine Trust spokesperson tells Bustle. Other factors also seem to influence stroke risk with modern combined pills, too; for instance, a 2010 study found that active smokers who have migraines have higher stroke risk when they use the combined pill than non-smokers.
Contraception that contains estrogen also carries another risk for women who experience aura with migraines. "Women with a history of migraine with aura also appear to be at an elevated risk of deep vein thrombosis," explains the American Migraine Foundation. "Estrogen-containing oral contraceptives also increase the risk of DVT, so women who have a history of blood clots, a family history of blood clots, or previous spontaneous abortions, should be further evaluated before being placed on an estrogen-containing oral contraceptive pill."
If you have a history of aura with migraines, current medical advice says to avoid all estrogen-heavy medications. "Women with this history should not take any type of estrogen, including those in birth control pills," Dr. Graves tells Bustle. However, some women who need high-estrogen medication for other symptoms, including polycystic ovary syndrome or the treatment of ovarian cysts, may have to choose between these health risks or the health risks of not managing their PCOS if they also get migraines with aura. This is one reason of many it's so important to talk with all your doctors — i.e., both your neurologist and your ob/gyn — about all the medication you're taking, and what you're taking it for.
The link between contraception, hormones and migraines is a complicated one. The good news is that for some women, continuous contraception can help avoid menstrual withdrawal migraine — but for others, low-estrogen or non-hormonal contraception are the best options to avoid complications. If you do experience migraines, particularly if they also come with auras, it's crucial that you mention this when evaluating the best birth control options with your medical professional. That way, you can get the contraceptive aid you need without incurring dangerous side effects.