This information is taken from the Evidence Based Birth Website compiled by Rebecca Dekker, PhD, RN, APRN

History of Fetal Monitoring

The first use of a device to listen to the adult heart rate was by French physician René Théophile Hyacinthe Laënnec in 1816 (Lewis et al. 2015), who invented the stethoscope. The story goes that he was too embarrassed to place an ear on a young woman’s chest to hear her heartbeat. So instead, he rolled sheets of paper into a tube and listened through this device. The paper listening tool was later made in wood to become the first wooden stethoscope.

It is thought that the fetal heartbeat was first heard in the middle of the 17th or 18th century by placing an ear to the mother’s abdomen. However, in 1822, fetal heart rate monitoring during labour became generally accepted with Lejumeau de Kergaradec’s use of the stethoscope (Obladen 2018). The first fetal electrocardiogram (EKG) recording took place in 1906 (Heelan 2013). In 1958, Dr Hon from Yale University first identified fetal distress by monitoring the fetal heart rate continuously through the mother’s abdomen (Hon 1958).

Continuous electronic fetal heart rate monitoring was introduced into hospitals in the 1970s without evidence from clinical trials, but with a strong marketing push from the monitoring industry (Obladen 2018). The machine was marketed as a scientific breakthrough that could predict fetal distress and bring an end to cerebral palsy—still the most common motor disability in childhood (CDC 2018). It was embraced by most obstetricians and nurses.

Women were not informed at the introduction of EFM in the 1970s that its use was totally experimental. Today, the use of continuous EFM machines is widespread, although, as you will see, it is still lacking evidence of benefits (Sartwelle et al. 2017). EFM was used among 45% of labouring women in 1980, 62% in 1988, 74% in 1992, and 85% in 2002 (ACOG 2009). Today, as we mentioned earlier, the rate of EFM during labour is around 90%. As the use of EFM during labour increased, so did the Cesarean rate, and it is possible that these two trends are connected. Between 1970 and 2016, the Cesarean rate in the U.S. increased from 5% to 32%. And “non-reassuring fetal heart tones” became the second most common reason for first-time Cesareans in the U.S. (ACOG 2017, #184). 

What Are Some of the Current Guidelines on Fetal Monitoring?

In the United States, the American College of Obstetricians and Gynecologists (ACOG) has endorsed hands-on listening as an “appropriate and safe alternative” to electronic fetal monitoring for labouring people without complications (ACOG 2009). They strengthened this position in a 2017 Committee Opinion called “Approaches to Limit Intervention During Labor and Birth,” where they state that “Continuous EFM has not improved outcomes for women with low-risk pregnancies” and recommend that care providers should “Consider training staff to monitor using a handheld Doppler device…which can facilitate freedom of movement and which some women find more comfortable” (ACOG 2017, #687). ACOG states that hands-on listening may not be appropriate for people at increased risk of complications such as those with meconium staining, bleeding during labour, suspected fetal growth restriction, preeclampsia, prior Cesarean, type 1 diabetes, or receiving Pitocin.

The clinical bulletin of the American College of Nurse Midwives (ACNM) states that hands-on listening—not electronic fetal monitoring—should be the preferred method of fetal monitoring in people at low risk for complications (ACNM 2015).

The Society of Obstetricians and Gynecologists of Canada state that there is no evidence to justify the use of continuous EFM in routine practice, and that hands-on listening is the preferred method of fetal monitoring for low-risk women (i.e., pregnant people at term with a single healthy baby, with spontaneous onset of labor, no previous Cesareans, and no maternal, pregnancy, or labor complications) (Liston et al. 2007).

In the United Kingdom, the National Institute for Health and Care Excellence (NICE) guidelines advise care providers not to offer EFM to women at low risk of complications during labour (NICE 2017). Instead, the guidelines suggest that low-risk labouring people be offered hands-on listening with either a Pinard fetal stethoscope or a Doppler ultrasound. If the fetal heartbeat is abnormal, they recommend that first steps should be listening more frequently and assessing the mother’s overall condition, such as her position, hydration, and other maternal observations. Continuous EFM is recommended if the fetal heartbeat remains abnormal, but the mother should be offered hands-on listening again after 20 consecutive minutes of normal EFM readings. Like ACOG, NICE guidelines also recommend EFM for people with certain risk factors, including those receiving Pitocin.

Different guidelines list different reasons why certain people should not have hands-on listening and instead have EFM. Whenever there is a reason not to do something, that reason is called a “contraindication.” Contraindications that have been suggested for hands-on listening include multiples, breech, high body mass index (BMI), prior Cesarean, post-term pregnancy, pre-term labour, premature rupture of membranes, and the use of Pitocin (Bailey 2009). However, these contraindications are based on clinical opinion, since there is no supporting evidence from studies that have compared EFM with hands-on listening in these specific groups. Although we know that people with certain risk factors have a higher risk of fetal complications during labour, we don’t know for certain if continuous EFM actually benefits these births over hands-on listening. The overall findings of the 2017 Cochrane review and meta-analysis applied to both “high-risk” and “low-risk” participants—everyone experienced fewer newborn seizures with continuous EFM but at the cost of higher rates of Cesarean.

Most guidelines recommend continuous EFM for people in labour who have had a prior Cesarean. This is because the most common sign of uterine rupture is fetal heart rate abnormality. Abnormal fetal heart rate patterns occur with about 70% of cases of uterine ruptures (ACOG 2017, #184). We only found one study that compared continuous EFM versus hands-on listening in people with a history of Cesarean, but unfortunately this study was too small (100 mothers) to offer any useful evidence about EFM vs. hands-on listening and the risk of uterine rupture (Madaan and Trivedi 2006). You would need about 12,000 people in each group in order to find a difference in the rate of uterine rupture between groups (Bujold et al. 2005).

There is much to consider when it comes to monitoring in Labour. To read the full article on Fetal Monitoring in Labour - please visit Evidence Based Birth.