A pregnant woman was performed hemodialysis 3 times a week from early
gestation. At 30 weeks of gestation, fetal growth and amniotic fluid v
olume were normal. We performed 3-hour hemodialysis 6 times a week. Ce
sarean section was performed at 38 weeks of gestation, she delivered a
healthy neonate weighing 2575 g. During hemodialysis, we performed Do
ppler flow velocimetry on the umbilical artery. The resistance index r
evealed a remarkable decrease after 1.5 hour hemodialysis. But it reco
vered 3 hours of administration as well as after completion of treatme
nt. We speculated this change in the resistance index of the umbilical
artery was caused by transient maternal hypovolemia.