Used as an adjunct to electrical fetal monitoring.
Attempts to improve the knowledge of he fetal condition by continuously measuring fetal oxygen saturation in the presence of a nonreassuring fetal heart rate pattern.
A specialized sensor is inserted through the dilated cervix after membrane rupture and is placed against the fetal face permitting measurement of fetal oxygen saturation during the labor process.
A comparison of 1010 women with labor complicated by a nonreassuring fetal heart rate pattern were randomly assigned to electronic fetal monitoring alone or electrical fetal monitoring plus fetal oximetry resulted in a reduction in the rate of cesarean delivery from 10.2-4.5%, respectively. (Garite)
In a study by Bloom et al of more than 5000 deliveries intrapartum fetal oxygen saturation monitoring had no significant effect on the rate of Cesarean delivery overall and particularly when a nonreassuring fetal heart rate or dystocia was present.
Low oxygen saturation was a common finding in women with fetal heart rate abnormalities and in women with normal fetal heart rate patterns, explaining that fetal oximetry did not benefit the interpretation of electronic fetal heart rate patterns.