[Ruptured arteriovenous malformation during pregnancy with special reference to diagnostic X-ray exposure.  Case report]. 
A 32-year-old female (gravida 2, para 2) was admitted at 15 weeks of gestation with a chief complaint of left homonymous hemianopsia accompanied by frontal headache.  Computed tomography scan and cerebral angiography were performed with the lead shield and probe for X-ray exposure placed on the patient's body.  Angiography revealed an arteriovenous malformation (AVM) located in the posterior part of the right temporal lobe.  Total dose of the diagnostic X-ray radiated to the fetus was measured 2.5 mrem at the most.  The AVM and the hematoma were totally removed successfully at 19 weeks of gestation.  A male infant weighing 3180 g was delivered at full term by cesarean section without congenital anomalies and he has been growing up without mental deficits.  These results suggest that diagnostic X-ray examination during pregnancy has little risk and that surgical treatment should be given to the mother immediately after the rupture of an AVM if she is in good condition and the gestational date is past 12 weeks.