Novel Maternal Blood Test Can Detect Fetal Oxygen Levels

Measuring the amount of hypoxia-induced mRNA in maternal blood is clinically correlated with the degree of fetal hypoxia in utero, according to a study published Dec. 9 in BMC Medicine. Using such a biochemical or molecular marker could be a new, direct strategy to monitor fetal hypoxia in utero, and researchers say the novel noninvasive maternal blood test represents a great advance in quantitatively measuring fetal danger from hypoxia both during labor or resulting from severe, chronic fetal growth restriction. Current tests (cardiotocograph, ultrasound, Doppler waveform velocimetry analysis) can indirectly identify hypoxic fetuses but not the severity of fetal acidemia (fetal blood pH/lactate concentrations), which can have detrimental birth outcomes including stillborn and severe perinatal injury and disability. Serial samples of maternal blood were collected prior to induction and commencement of uterine contractions, at commencement of the second stage of labor including full dilatation, and at delivery. The researchers correlated hypoxia-induced mRNA in the samples with the degree of fetal umbilical artery blood samples and placental biopsies collected immediately after delivery. Two cohorts were evaluated—one group with acute fetal hypoxia caused by induction of labor (n=30) and one group with chronic fetal hypoxia due to severe, preterm growth restriction (n=20 […]