Operative delivery in a parturient with HAE already on C1-INH q3d prophylaxis – when to give an extra dose? I am following a woman with HAE who has required prophylactic C1-INH during pregnancy for increased frequency and severity of symptoms that reliably occur with each pregnancy and improve between pregnancies. To my knowledge, current guidelines address when to prophylax treatment-naïve women for operative delivery, but do not address whether or when to give an extra dose in parturients already on chronic prophylaxis. She infuses every 3 days. The half-life of C1-INH is about 16h on the low end. If she requires operative delivery more than 24 hours after her regular infusion, how do high volume HAE centers practice with respect to giving an extra dose of Cinryze in the operating room?


I checked with a high volume HAE center and received the following response. In general, women with HAE do not swell as a consequence of labor and delivery. Therefore, we do not typically give a prophylactic treatment before delivery unless she has a known history of swelling with delivery. With that said, it is always good practice to have an additional dose of C1INH available in the delivery room to give if the patient begins to swell. If the patient is to have a C-section, then I would be inclined to give an extra dose of C1INH shortly before the procedure unless she receives her scheduled dose within 12 hours of the procedure.

You state that her HAE improves between pregnancies. If she does not take C1INH prophylaxis between pregnancies, I would not taper the prophylaxis off too quickly as there is a significant risk of swelling in the postpartum period as the hormonal levels re-equilibrate. She should be closely observed for swelling for 3 days after birth.

Caballero et al, International Journal of Women’s Health, Sept 2014

Dr. Jacqueline A. Pongracic, FAAAAI
Dr. Bruce Zuraw

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