Birth Control and Blood Clots: What Women Need to Know

Hailey Bieber never saw it coming.

One day she’s modeling for international cover stories in glossy magazines, and the next she’s being rushed to the hospital for a mini-stroke. How could a young, 25-year-old woman—one who is physically fit and active, often posting about her adventures hiking and kayaking with husband Justin Bieber—have a stroke? She says birth control pills were a factor.

In a video posted April 27, Bieber tells her story. “I had a very scary incident on March 10,” she says. “Basically, I was sitting at breakfast with my husband, having a normal day, a normal conversation. And we were in the middle of talking and all of a sudden I felt this really weird sensation that kinda traveled down my arm from my shoulder all the way down to my fingertips and it made my fingertips feel really numb and weird.”

She goes on to reveal that she couldn’t speak. “The right side of my face started drooping, I couldn’t get a sentence out.” She says, “I thought I was having a stroke.”

“Definitely the scariest moment of my life,” Bieber adds.

“They did some scans and were able to see that I had suffered a small blood clot to my brain, which they labeled and categorized as a transient ischemic attack (TIA),” she said. “It’s like having a mini stroke, except my body was able to resolve it pretty quickly.”

“They did come to the conclusion of why they think I had a blood clot,” she explains. “I had just recently started birth control pills, which I should have never been on because I’m somebody who suffered from migraines.” She added that she also recently had Covid and had recently gone on a long flight from Paris to back, which created “the perfect storm” for the blood clot. Doctors also found a patent foramen ovale (PFO) in her heart, which allowed the clot to escape and move up into her brain.

Thankfully, she’s OK, but her story is scary for the 11 million women currently taking an oral contraceptive in the U.S. How likely is it to develop a blood clot or a stroke from your birth control pill? Here’s what we know.

Most strokes are caused by blood clots

What is a stroke, exactly? According to the American Stroke Association, an ischemic stroke (which accounts for 87% of all strokes) occurs when “a vessel supplying blood to the brain is obstructed.” This is caused by a blood clot.

Birth control pills do increase your risk of blood clots

Combined hormonal contraceptives (which include estrogen and progestin) are an effective method to prevent pregnancy. These include birth control pills, the birth control patch, and the vaginal birth control ring.

The American College of Obstetricians and Gynecologists (ACOG) says combined hormonal contraceptives are safe for most women. However, this type of birth control has been linked with a small increased risk of deep vein thrombosis (DVT), heart attack and stroke.

A 2015 study by Loyola University Health System found that taking birth control pills increases the risk of ischemic stroke 1.9 times, to 8.5 strokes per 100,000 women. So although it does slightly increase your chance, the overall number of birth-control related strokes is still very small.

Most common symptoms of birth control are relatively mild

The most common side effects of combined hormonal birth control are:

Headaches
Nausea
Breast tenderness
Breakthrough bleeding

Some women are more susceptible to developing DVT, heart attack or stroke

“Some medical conditions can increase your risk of complications from hormonal birth control,” Amy Roskin, OB-GYN and chief medical officer of Favor, tells Motherly. “Examples include a history of stroke, migraines with aura, heart disease, blood clots in the leg or lung, or breast cancer. With these conditions, it’s likely that hormonal birth control containing estrogen may not be a fit for you.”

Other risk factors that make some women more likely to develop DVT, heart attack, or stroke, according to the ACOG, include:

If you are 35 years or older and smoke more than 15 cigarettes a day.
If you have multiple risk factors for cardiovascular disease, such as high cholesterol, high blood pressure, and diabetes.
If you have a history of stroke, heart attack, or DVT.
If you have a history of migraine headaches with aura.
If you are taking pills containing a progestin called drospirenone.
If you are using the patch.

Additionally, women who have given birth within the last three weeks should not use a combined hormonal contraceptive because the risk of DVT is higher in the weeks after childbirth. If you have additional risk factors for DVT, you should wait until 4-6 weeks after delivery to begin combined hormonal birth control.

“Ultimately, if you’re at all concerned that the form of hormonal birth control you’re using might not be the best fit, I recommend speaking with your primary care physician,” adds Dr. Roskin. “If this is not possible, speaking to a physician via a telehealth platform like Favor can provide support and facilitate any changes that might need to be made to your prescription.”

Hailey Bieber had a history of migraines with aura

“Hailey Bieber had a history of migraines with aura—flashing lights or blind spots,” says Dr. Roskin. “This condition can increase the risk of complications like a stroke in people who are taking combination (estrogen-containing) birth control pills.”

A 2017 study published in the Journal of Headache and Pain found that combined hormonal birth control can increase the risk of ischemic stroke in women with migraines, specifically migraine with aura.

“If you’re experiencing these kinds of migraines, or other health conditions like high blood pressure that’s not well managed, a history of pulmonary embolism, or a history of breast cancer or heart disease, speak with a licensed medical physician in your area or a telehealth provider through a service like Favor, who can talk through your birth control options and share which form might be best for you,” she says.

Dr. Roskin adds, “Your doctor might choose to prescribe you another type of birth control to decrease the risk of health complications.”

If you are worried about getting a stroke from taking hormonal birth control, know that it is “unlikely,” according to Dr. Roskin.

What type of birth control has a lower risk of stroke?

A 2019 study in Frontiers in Neurology found that a higher estrogen dose of contraceptive at a longer duration increased the risk of a stroke. Luckily for combined oral contraceptive pill users, a 2018 study showed that modern birth control pills have lower doses of estrogen than older formulas.

You may also consider progestin-only birth control options, like the progestin-only pills, implants, or progestin IUD. “Some non-hormonal options are a good solution,” says Dr. Roskin. “These can include everything from contraceptive gels like Phexxi to copper IUDs that are associated with a lower risk of stroke.”

How do you know if you are experiencing a blood clot or stroke?

Aside from the medical conditions that could increase your risk of blood clots while taking hormonal birth control, there are a few other signs you should change your birth control.

“If you’re on hormonal birth control, pain, swelling, or redness behind your knee or calf can be a sign of a blood clot,” stated Dr. Roskin.

The National Blood Clot Alliance lists the following symptoms of a blood clot in your leg or arm:

Swelling, pain, or tenderness not caused by injury
Skin that is warm to the touch
Redness or discoloration

These are the symptoms of a blood clot in your lung:

Difficulty breathing
Chest pain that worsens with a deep breath
Coughing up blood

The National Stroke Association offers these F.A.S.T. warning signs to spot a stroke:

F = Face Drooping – Does one side of the face droop or is it numb? Is the smile uneven?
A = Arm Weakness – Is one arm weak or numb? Does one arm drift downward when arms are raised?
S = Speech Difficulty – Is speech slurred?
T = Time to call 911

Other symptoms of a stroke include:

Numbness
Confusion
Trouble seeing
Trouble walking
Severe headache with no known cause

Call 911 or go to the emergency room if you experience these symptoms.

There is a higher chance of getting a blood clot during pregnancy and the postpartum period

During pregnancy and the postpartum period, you have a higher risk of developing a blood clot than you do when taking combined hormonal birth control.

According to the CDC, women are at a higher risk for blood clots during pregnancy, childbirth, and up to three months after delivering a baby. Pregnant women are five times more likely than non-pregnant women to experience a blood clot. The American Heart Association states this is due to an increase in platelets and clotting factors while you’re pregnant, as well as the possibility of the uterus compressing the veins and slowing blood flow.

Additionally, the American Stroke Association says that pregnant women are three times more likely to have a stroke than non-pregnant women of the same age, compared to women who take birth control pills, who are only two times as likely to have a stroke. Overall, 1 in 5 women will have a stroke, and Black women have the highest prevalence of stroke.

Taking birth control to prevent unwanted pregnancies may slightly increase your risk of stroke, but not as much as getting pregnant. If you are worried about it, or if you have factors that could increase your risk of stroke, talk to your health care provider about alternative contraceptive options.

Featured Expert

Amy Roskin is an OB-GYN and the chief medical officer of Favor.

Sources

Carlton C, Banks M, Sundararajan S. Oral Contraceptives and Ischemic Stroke Risk. 2018. Stroke, 49(4). doi: 10.1161/strokeaha.117.020084.

Devis P, Knuttinen MG. Deep venous thrombosis in pregnancy: incidence, pathogenesis and endovascular management. 2017. Cardiovascular diagnosis and therapy, 7(Suppl 3), S309–S319. https://doi.org/10.21037/cdt.2017.10.08

Hurt K, Joseph; et al., eds.. The Johns Hopkins manual of gynecology and obstetrics (4th ed.) 2012. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins. p. 232. ISBN 978-1-60547-433-5.

Li F, Zhu L, Zhang J, He H, Qin Y, Cheng Y, Xie, Z. Oral Contraceptive Use and Increased Risk of Stroke: A Dose-Response Meta-Analysis of Observational Studies. 2019. Frontiers in neurology, 10, 993. https://doi.org/10.3389/fneur.2019.00993

Loyola University Health System. Birth control pills pose small but significant stroke risk. ScienceDaily. Updated: 2015, September 18. Sacco S, Merki-Feld GS, Ægidius KL, Bitzer J, Canonico M, Kurth T, Lampl C, Lidegaard Ø, Anne MacGregor E, MaassenVanDenBrink A, Mitsikostas DD, Nappi RE, Ntaios G, Sandset PM, Martelletti P; European Headache Federation (EHF) and the European Society of Contraception and Reproductive Health (ESC). Hormonal contraceptives and risk of ischemic stroke in women with migraine: a consensus statement from the European Headache Federation (EHF) and the European Society of Contraception and Reproductive Health (ESC). J Headache Pain. 2017 Oct 30;18(1):108. doi: 10.1186/s10194-017-0815-1. Erratum in: J Headache Pain. 2018 Sep 10;19(1):81.