Background: Fetal subdural hematoma is a rare condition not considered a complication of Crohn disease in pregnancy.
Case: A young woman with a diagnosis of Crohn disease presented at 22 weeks' gestation with diarrhea and melena for 3 weeks. Dietary and medicinal therapies were begun. At 28 weeks' gestation, fetal ultrasonography showed an intracranial mass, which was seen to expand on serial ultrasound and magnetic resonance imaging studies. A hematoma was suspected, and, although the mother had no overt hemorrhagic manifestations, maternal vitamin K deficiency was diagnosed by enzyme immunoassay and corrected. After cesarean delivery at 36 weeks' gestation, the newborn was normal, but magnetic resonance imaging showed a chronic subdural hematoma.
Conclusion: Maternal vitamin K deficiency in active Crohn disease might cause fetal hemorrhage. Monitoring of vitamin K status during pregnancy with Crohn disease seems warranted.