Is It Safe to Get Pregnant With HHT? Risks & Management

Yes, it is generally safe for women with Hereditary Hemorrhagic Telangiectasia (HHT) to get pregnant, and most go on to have healthy pregnancies and healthy babies. However, because HHT affects your blood vessels, pregnancy is considered “high-risk.” Careful planning, proactive screening, and a multidisciplinary healthcare team — typically including a maternal-fetal medicine specialist — are essential to ensure your safety and the safety of your baby ^[1][2].

Why Does HHT Make Pregnancy High-Risk?

During a normal pregnancy, a woman’s blood volume increases by up to 50%, and her heart pumps harder to support the growing baby ^[1]. In women with HHT, these natural physiological changes can put extra pressure on existing arteriovenous malformations (AVMs) — abnormal tangles of blood vessels where arteries and veins connect directly without standard capillaries. This increased blood flow and pressure can cause AVMs to enlarge, significantly increasing the risk of them tearing or rupturing ^[3][4].

Managing Day-to-Day HHT Symptoms

While major AVM complications are rare, you are highly likely to experience changes in your typical HHT symptoms:

• Worsening Nosebleeds (Epistaxis): The increased blood volume and changes in nasal blood vessels during pregnancy often cause nosebleeds to become more frequent or severe ^[1].
• Anemia and Iron Deficiency: Pregnancy demands a huge amount of iron to support the baby. When combined with the chronic blood loss from HHT nosebleeds or stomach bleeding, you are at a very high risk for severe iron-deficiency anemia ^[1]. Your care team should monitor your iron and ferritin levels strictly and will likely recommend robust iron supplementation.

Essential Screenings: Lungs and Brain

Because of the risks associated with AVMs, the 2020 International HHT Guidelines strongly recommend proactive screening ^[1]. Ideally, these screenings should happen before you conceive, but if you are already pregnant, they should be done as early as possible. Importantly, screening should be repeated for every pregnancy, as AVMs can grow or change over time.

• Lung (Pulmonary) AVMs: This is the most critical screening. Ruptured lung AVMs can cause massive bleeding in the chest (hemothorax) or allow blood clots to pass into the brain, causing a stroke ^[3][4]. Screening is typically done using an ultrasound of the heart with bubbles, known as a transthoracic contrast echocardiography (TTCE) ^[5]. If lung AVMs are found, doctors strongly prefer to seal them off (a procedure called embolization) before you get pregnant ^[6]. If treatment is needed during pregnancy, it can often be done safely during the second or third trimester ^[7].
• Brain and Liver AVMs: Your care team will also recommend screening for AVMs in your brain and liver. Brain AVMs carry a risk of bleeding (hemorrhage) ^[8], and severe liver AVMs can complicate heart function ^[9]. Identifying these early helps your doctors tailor a safe management plan for delivery.

Labor, Delivery, and Epidural Precautions

Many women with HHT wonder if they will be required to have a C-section. In general, a vaginal delivery is safe for women with HHT, and C-sections are only performed for standard obstetric reasons.

When planning your delivery, your team will carefully consider pain management. An epidural (neuraxial anesthesia) is a common way to manage labor pain. Because HHT can cause AVMs in the spine, there is a theoretical risk of bleeding if a needle is placed into an unknown spinal AVM ^[10].

However, spinal AVMs are very rare, occurring in only 1-2% of HHT patients. The current international guidelines state that routine spinal MRIs are not required for most women before getting an epidural. Unless you have specific neurological symptoms, an epidural is generally considered safe ^[1]. If a spinal AVM is already known to be present, your team will take specialized precautions and may suggest alternative pain relief methods or general anesthesia to avoid the risk entirely ^[11].

Genetic Counseling and Family Planning

HHT is an autosomal dominant genetic condition ^[12]. This means that if you have HHT, there is a 50% chance of passing the genetic mutation to each of your children ^[13][12].

Many women with HHT choose to consult a genetic counselor before getting pregnant. A counselor can help you understand these risks and discuss reproductive options, such as Preimplantation Genetic Testing (PGT) ^[14][15]. PGT is performed during in vitro fertilization (IVF) to test embryos for the HHT gene mutation, helping families make informed decisions about their reproductive options, such as choosing to implant an embryo without the HHT gene.

Warning Symptoms to Watch For

While most pregnancies go well, you must recognize the signs of a potential complication. Seek immediate emergency medical care if you experience:

• Sudden or severe shortness of breath
• Coughing up blood (hemoptysis)
• A sudden, exceptionally severe headache
• Any sudden numbness, weakness, vision changes, or difficulty speaking

These can be signs of a ruptured AVM in the lungs or brain and require rapid medical intervention ^[3][16].