Does the presence of fetal hemoglobin affect the accuracy of FSpO2 readings?
Fetal hemoglobin (HbF) does have a slightly different light absorption characteristic than adult hemoglobin, and can be expected to have some level of influence on FSpO2 readings. As demonstrated with mathematical modeling4, fetuses with higher concentrations of HbF will usually cause the system to read slightly lower FSpO2 values than fetuses with lower concentrations of HbF. However, due to differences in fractional HbF content, the relative difference in FSpO2 readings is on the order of 1% and is not clinically significant.
