Hormonal changes are known triggers for hereditary angioedema (HAE) attacks. So it’s probably not surprising that menstruation and pregnancy can affect the frequency and severity of your attacks.

It’s incredibly important to be aware of how hormone changes impact your condition. Read on to find out how periods, birth control, menopause, and pregnancy affect HAE.

Female hormones and HAE

HAE affects both men and women, but women are more likely to have symptoms. Female sex hormones, like estrogen, are the likely culprit. They are thought to increase the creation of a peptide known as bradykinin.

Bradykinin is a vasodilator, a compound that opens up (dilates) the blood vessels. It increases the amount of fluid leaking through the walls of the blood vessels into tissues. The increase in bradykinin is typically regulated by another protein. This protein is called C1 esterase inhibitor. People with HAE don’t have enough C1 esterase inhibitor to control this process.

Excessive fluid then accumulates in the body’s tissues. This results in the swelling associated with an HAE attack.

Menstruation

Many women begin to experience attacks for the first time when puberty begins and they get their first periods. Some women with HAE also find that attacks increase right before their menstrual period each month.

Birth control

For the majority of women, birth control pills that contain estrogen are linked to an increase in both the frequency and severity of HAE attacks. Women with HAE should instead take a non-estrogen option. Non-estrogen birth control options include a progestin-only pill or an intrauterine device (IUD). These alternatives are usually well tolerated by women with HAE.

Some women with HAE don’t experience any issues from an estrogen-based birth control pill. In this case, you can continue taking them.

Pregnancy

The way that pregnancy affects HAE symptoms can be unpredictable. About one-third of women with HAE experience more attacks. Another third of women experience fewer attacks. One-third don’t experience any changes at all.

Women with HAE don’t have a higher risk of infertility or miscarriage. But women who face worse symptoms during pregnancy usually have an increase in attacks more often in the third trimester. If this happens, your doctor may give you C1 inhibitor concentrate during labor and delivery. Your doctor may recommend a preventative treatment, such as tranexamic acid. A severe attack can be treated with a C1 inhibitor concentrate.

If your condition is less severe during the course of your pregnancy, you likely won’t need to take a preventative treatment. But it should be available in the delivery room just in case. Your doctor may also recommend that you get an epidural during labor.

Breastfeeding

Research shows that many women with HAE experience an increase in both the amount and severity of attacks right after giving birth. Breastfeeding isn’t the cause. But an increase in attacks after childbirth can have a huge impact on your breastfeeding routine.

You may want to consider taking a preventative treatment during this time. Talk to your doctor about treatments that are safe for your baby.

Menopause

Menopause is yet another time in a woman’s life where a change in hormone levels can have an effect on HAE symptoms. Like pregnancy, it’s difficult to predict exactly what those changes will be. A little more than half of women with HAE experience no changes during menopause. About a third of women experience an increase in attacks. A small percentage of women see an improvement in their symptoms.

“Estrogen-dependent” HAE

Women with the rarest form of HAE (type 3) have a mutation in their factor XII gene. These women experience attacks almost only during periods of high estrogen. For this reason, type 3 HAE used to be known as “estrogen-dependent” HAE, but this term is no longer used.

It’s now known that there are several different gene mutations that cause type 3 HAE. Estrogen levels don’t affect symptoms in all type 3 HAE patients.

Next steps

Women with HAE should carefully select their birth control. They should also manage their pregnancies carefully and consider their risk of having an attack before their periods. But every woman with HAE is different. Some are sensitive to changes in their hormone levels, while others aren’t.

If you’re pregnant or planning on becoming pregnant, you should speak with your doctor in advance. Speak to your obstetrician as well about creating an HAE treatment plan.

HAE is an inherited condition, and there is a chance you’ll pass it on to your child. Therefore, you may also wish to speak to a genetic counselor.