I know most women's labor is monitored by a machine. What is it looking for?
The expert answers
The machine is an electronic fetal monitor. The purpose of the machine is to monitor the baby's heart rate in relation to the contractions during labor. Two stretchy belts are put around the woman's belly. One belt has a transducer to measure her contractions and the other measures the baby's heart rate.
viewed together your health care provider can assess how the baby
is tolerating labor. The belt measuring mom's contractions is a
pressure sensitive device which senses the change in shape of the
uterus during a contraction. The belt measuring the baby's heart
rate uses ultrasound to detect the motion of the baby's heart.
This is much like the Doppler device that your health care
provider uses to listen to the baby's heartbeat during office
In general, when you arrive at the hospital in labor your health care provider will monitor you for approximately 20 minutes and then intermittently thereafter provided the baby is tolerating labor well. Some health care providers use continuous fetal monitoring throughout labor. Some hospitals have telemetry devices so that you can be monitored even when out of bed. However, if you have medication, either for pain relief, such as an epidural, or to augment your labor your health care provider will want to monitor you and the baby more closely and then you may required to have monitoring throughout your labor.
In order to monitor the baby even more closely another type of monitor is used. This is an internal fetal monitor which looks like a small wire. It is inserted through your vagina into the baby's scalp. In order to use this type of monitoring your bag of waters must be broken. To monitor the contraction's strength inside the uterus an intrauterine pressure catheter is used.
Each of these monitoring devices prints out a graphic record of the contractions and the baby's heartbeat that can be seen in your room and also at the nurse's station.
- Kira Smith, M.Ed, ICCE
Editor's note: There is some controversy over the use of electronic fetal
monitoring, as studies have shown that it increases a woman's risk of
cesarean section. For example, if the transducer is not able to pick up the
baby heartbeat well (which might happen if the mother or baby moves around),
this could result in a misinterpretation of the baby's health status.
Unnecessary interventions, including cesarean delivery, may result.