In many hospitals, a baby's heartbeat is monitored throughout labor, making it possible to detect any problems early so they can be resolved. There are two types of fetal monitoring during labor— external fetal monitoring and internal fetal monitoring.
External fetal monitoring can be done before your membranes rupture. A belt with a receiver is strapped to your abdomen, and it records the baby's heartbeat.
Internal fetal monitoring is the more precise method of monitoring the baby. An electrode is placed on the fetal scalp to record the fetal heart rate.
Fetal Blood Sampling
This is another way of evaluating how well a baby is tolerating the stress of labor. Membranes must be ruptured, and the cervix must be dilated at least 2cm. An instrument is applied to the scalp of the baby to make a small nick in the skin. The baby's blood is collected in a small tube, and its pH (acidity) is checked.
The pH level can help determine whether the baby is having trouble during labor. Results help the physician decide whether labor can continue or if a Cesarean section needs to be done.