HHT Does Not Directly Impair Fertility
HHT itself does not cause infertility or reduce fertility rates in affected individuals. The disease is an autosomal dominant vascular disorder that primarily affects blood vessels, not reproductive organs or hormonal function 1, 2.
Key Points About HHT and Reproduction
Fertility Remains Normal
- Women and men with HHT have normal fertility rates, as the genetic mutation affects vascular endothelial cells rather than reproductive tissues 3, 4
- The 50% inheritance risk for each child reflects the autosomal dominant pattern, not reduced conception rates 1, 2
Pregnancy Outcomes Require Careful Management
While fertility is unaffected, pregnancy in HHT women carries specific risks:
- Miscarriage rates are approximately 20%, which is within the range of the general population 5
- Maternal mortality is estimated at 1.0% of pregnancies in screened populations, with severe complications occurring in 2.7-6.8% of pregnancies 6
- Most complications occur in unscreened and untreated patients, particularly in the second and third trimesters 5, 6
Critical Pregnancy Complications
The serious risks relate to arteriovenous malformations, not fertility:
- Pulmonary AVM complications include hemothorax (most common), hemoptysis, and severe hypoxemia 5, 6
- Hepatic AVM complications can cause high-output heart failure and hepatobiliary necrosis 6
- Cerebral AVM rupture leading to intracranial hemorrhage has been reported 5, 6
- Women notice increased epistaxis frequency and new telangiectases during pregnancy 5
Clinical Management Approach
Pre-Conception Counseling
- Provide genetic counseling to all HHT patients of childbearing age about the 50% inheritance risk 1
- Screen for arteriovenous malformations before pregnancy, particularly pulmonary, hepatic, and cerebral AVMs 6, 3
- Explain that screened and treated HHT patients have normal life expectancy (75.9 years), comparable to controls 7
Medication Considerations Before Conception
- Discontinue tranexamic acid several days before attempting conception (half-life 2-8 hours) 8
- Stop androgenic anabolic steroids 2 months before conception due to risk of fetal sexual differentiation abnormalities 8
- Continue plasma-derived C1-inhibitor if needed (though this is for hereditary angioedema, not HHT) 8
Pregnancy Monitoring
- Classify all HHT pregnancies as high-risk regardless of symptom severity 6
- Monitor closely in the second and third trimesters when complications peak 5, 6
- Epidural/spinal anesthesia can be performed safely (used in 50% of deliveries without complications), though screening for spinal AVMs is theoretically prudent 5
Post-Partum Care
- Close follow-up for at least 72 hours after delivery by staff familiar with HHT 8
- Inform patients about increased risk of postpartum swelling and provide treatment plans 8
Common Pitfalls to Avoid
Do not confuse pregnancy risk with infertility. HHT patients conceive normally but require specialized prenatal care 5, 6.
Do not delay AVM screening until pregnancy occurs. Pre-pregnancy screening and treatment of pulmonary, hepatic, and cerebral AVMs dramatically reduces maternal morbidity and mortality 6, 7.
Do not perform liver biopsy in any HHT patient due to catastrophic hemorrhage risk from hepatic vascular malformations 8, 1.