Transcutaneous fetal oxygen tension and fetal heart rate pattern preceding fetal death. Case report.

Simultaneous cardiotocography (CTG) and transcutaneous PO2 (tcPO2) measurements were made in a pregnancy complicated by membrane rupture and cord prolapse at 27 weeks gestation. A Caesarean section was not done because the fetus was judged to have little chance of survival and to be at very high risk of severe brain damage if it did. The fetus weighed 830 g and the CTG changes preceding fetal death were similar to those described by others. The tcPO2 was zero for periods of a few seconds to 20 minutes at 1 to 2 hours before fetal death, and the tcPO2 was constantly zero during the last 50 minutes of fetal life. Tracings showing the tcPO2/CTG changes preceding fetal death are reproduced.