Can birth control increase the risk of stroke?

Birth control containing estrogen can slightly increase the risk of stroke for some people.

According to a 2021 study, systemic hormonal contraceptives can increase the risk of stroke and heart attack by 1.6 times. Examples of systemic birth control include:

Planned Parenthood states that although most people will not experience problems, the birth control shot can increase the risk of blood clots, which can lead to stroke or damage the heart and lungs.

They also say that some people may have an increased risk of stroke if they use birth control containing estrogen, which includes the birth control patch.

It is important to remember that for most people, hormonal birth control is a safe and effective method of contraception. However, as with all medications, they can carry certain risks and side effects.

A person will be able to work with a doctor to determine which form of birth control is best for them.

Higher doses of estrogen have an association with a higher stroke risk. A 2019 review found that oral contraceptives with higher estrogen dosage were linked to an increased stroke risk, including both ischemic and hemorrhagic stroke.

However, according to a 2018 review, modern combined oral contraceptives contain a lower dose of estrogen, which reduces the risk of stroke compared to older types of oral contraceptives.

People who are using combined oral contraceptives and have other risk factors for stroke, such as smoking or high blood pressure, have a higher risk of stroke.

According to a 2019 review, there may be around a 20% increased risk of ischemic stroke and total stroke with every 10 micrograms (μg) of estrogen or with each 5-year use of oral contraceptives.

Once a person has stopped using oral contraceptives, the risk may decrease by 20% every 5 years.

The study suggests longer duration of use and higher levels of estrogen increase the risk of stroke.

A 2022 study suggests the stroke risk may be highest in the first year of oral contraceptive use. After the first year, the risk may be reduced and be similar to the risk in nonusers.

The stroke risk from combined oral contraceptives is lower than the risk of stroke with pregnancy.

Oral contraceptives with higher levels of estrogen may have the highest risk of stroke.

Oral contraceptives with doses of estrogen of 50 μg or higher may increase the risk of stroke, although the risk may increase with each 10 μg increase of estrogen.

According to a 2018 review, nonhormonal forms of birth control and progestin-only birth control have no increased risk of stroke.

There is little data on the stroke risk of the transdermal patch and vaginal ring, which contain both progestin and estrogen, in the form of ethinyl estradiol.

Some research found no increased stroke risk of patches or vaginal rings containing estrogen or birth control with low dose ethinyl estradiol.

According to a 2018 article, nonsmokers with normal blood pressure using low dose combination oral contraceptives had a stroke risk per year of 8.5 per 100,000 people. This is compared to 4.4 per 100,000 people not using oral contraceptives.

According to a 2019 review, research suggests that oral contraceptives containing doses of estrogen of 50 μg or above may link to a risk of ischemic stroke. The review also suggests that total stroke risk may increase with each 10 μg of estrogen dosage.

Older combined oral contraceptives were high dose formulations containing 80–100 µg ethinyl estradiol, which is not commonly available now.

Current formulations for combined oral contraceptives typically contain low doses, usually between 30–35 μg of ethinyl estradiol.

Certain health-related factors can increase the risk of stroke in people using combined oral contraceptives. This includes:

Experts also recommend that those who have multiple stroke risk factors use nonestrogen or nonhormonal forms of contraception. This includes people who are ages 35 years or above, have migraine with focal neurological signs, and people who smoke.

Other risk factors for stroke include:

• diabetes
• hyperlipidemia
• obesity

A 2020 article states that stroke in young people is less common, but certain risk factors may contribute to stroke risk. One of these risks is birth control containing estrogen.

A combination of risk factors may increase the risk of stroke in young people. The combination of migraine with aura, combined oral contraceptive use, and tobacco use may increase the risk of stroke by around 9 times compared to people with none of these risk factors.

Ischemic stroke may be more common in younger females with migraine with aura who may not be likely to have traditional risk factors such as high blood pressure or diabetes.

Checking for any other risk factors for stroke may help to reduce the risk of stroke. This includes:

• a history of blood clots
• high blood pressure
• smoking
• overweight or obesity

Discussing contraceptive options and risk factors can help people make an informed decision. People can also opt for a nonestrogen form of contraceptive or nonhormonal contraceptives.

Hormonal birth control containing estrogen may increase the risk of stroke. The risk may be small, but people with other risk factors of stroke may have a higher risk.

People can discuss contraceptive options with a healthcare professional to assess their personal risk and to decide which is the safest option for them.