Prolonged fetal bradycardia secondary to maternal hypothermia in response to urosepsis.

Fetal bradycardia is a well-known response to maternal hypothermia, as induced at open-heart surgery, but heretofore has not been reported in conjunction with hypothermia from urosepsis. A 24-year-old Vietnamese woman admitted at 33 weeks estimated gestational age with pyelonephritis secondary to Escherichia coli developed several episodes of maternal hypothermia to 35-36 degrees C. During each episode of maternal hypothermia, the baseline fetal heart rate fell to 90-100 bpm, but with retained reactivity. During each episode, maternal vital signs were otherwise stable and oxygen saturation was normal as measured by pulse oximetry. Interpretation of fetal bradycardia during episodes of maternal urosepsis is complex. If seen in conjunction with maternal hypothermia, and in the presence of normal maternal cardiac and respiratory function, bradycardia is unlikely to represent fetal distress.