Hereditary angioedema and pregnancy.

BACKGROUND: Hereditary angioedema (HAE) is an autosomal dominant disease caused by a quantitative or functional defect in C1-esterase inhibitor (C1-INH). Patients with this deficiency present with episodes of angioedema which can be life-threatening. Studies examining HAE and pregnancy are scarce with little known about the interrelationship between the two.

OBJECTIVE: To examine the effect, and evaluate the clinical manifestations of HAE in pregnancy using retrospective interviews of affected women.

METHODS: Women with HAE who have undergone one of more pregnancies were identified throughout Australia using the national Australasian Society of Clinical Immunology and Allergy immunodeficiency database. Following informed consent, identified women were interviewed regarding their HAE status during pregnancy and the perinatal period using a questionnaire.

RESULTS: Seven women with a total of 16 pregnancies were identified. During the first trimester of pregnancy, more than ten attacks of angioedema were experienced in six of 16 pregnancies. During the second trimester only in three of 16 pregnancies did women experience greater than ten attacks. During the post-partum period, four of seven women experienced increased frequency and severity of attacks as compared to the pre-pregnancy state. For two of four patients, this impacted on their breast-feeding routine.

CONCLUSION: Our study showed that women with HAE have greatly reduced or absent attacks in the last two trimesters of pregnancy, although, during the post-partum period, the majority of women experienced increased frequency and severity of attacks.