G1

A 30 year old G1P0 woman with a history of mild intermittent asthma at 34 weeks gestation gets into a minor car accident. There are no noted injuries; fetal heart monitoring is normal. Routine labs are sent and her platelets are 110,000. She is asymptomatic and does not have bleeding or bruising. She's never had this problem in the past.

Challenge: What's the most likely etiology?

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