Which method is traditionally NOT used in the US to assess fetal hypoxemia during labor?

Pulsatile oximetry is traditionally not used in the US to assess fetal hypoxemia during labor. Instead, established methods such as fetal scalp pH monitoring and fetal heart rate monitoring are more commonly utilized.

Fetal scalp pH involves sampling the fetal blood from the scalp to determine acid-base balance, which can indicate hypoxemia if there is significant acidosis. Fetal heart rate monitoring tracks the heart rate patterns of the fetus, providing vital information about how well the fetus is tolerating labor and whether there are signs of distress.

While the use of an oximeter placed against the fetal cheek may not be the standard practice, it could potentially provide some data regarding oxygen saturation in specific situations. However, pulsatile oximetry has not been widely adopted in the standard protocols for monitoring fetal well-being during labor in the US, making it the correct choice as the method that is traditionally not used.