Who invented the fetal monitor

LeGaust was a colleague of Marsac, a physician of the province of Limousin, who is credited with first having heard the fetal heart.

He suggested auscultation to be of value in the diagnosis of pregnancy and twins and in determining fetal lie and presentation. The text contains many anecdotal examples of cases in which auscultation was clearly beneficial. In addition, Kennedy described the funic souffle for the first time. Rauth and Verardini 2 suggested vaginal stethoscopy as more valuable in the early detection of fetal life.

The development of the head stethoscope fetoscope is a story of controversy and professional jealousy. In , J. DeLee 4 , who was chief of staff at the same institution and who became a legend in American obstetrics for many contributions, published his report of a similar instrument. Although the order of publications is clear, DeLee claimed that he openly talked of this idea for many years preceding the Hillis publication.

Since the Cochrane analysis only included around 37, participants, there is a chance that continuous EFM has an effect on stillbirth that was not detected. If continuous EFM leads to a decrease in stillbirths during labor, it does not necessarily mean that continuous EFM should be used all the time for all laboring people. Any decrease in the risk of stillbirth during labor would be very small, especially among low-risk births, while the known increase in Cesarean rates with continuous EFM is very large Hornbuckle et al.

There have only been two randomized trials on this topic:. In one study, researchers in Sweden randomly assigned more than 4, low-risk participants to receive either continuous EFM or intermittent EFM Herbst and Ingemarsson They defined intermittent EFM as being on the monitor for 10 to 30 minutes every two to two-and-a-half hours during the active first stage of labor plus the use of hands-on listening every minutes in between EFM periods.

So, in other words, the intermittent EFM group also had hands-on listening. In the second stage of labor, all of the participants were monitored continuously with EFM. The researchers found no differences in any outcomes. There has only been one randomized, controlled trial that compared intermittent EFM alone with hands-on listening alone Mahomed et al. In this study, 1, low-risk participants giving birth at a hospital in Zimbabwe were randomly assigned to either intermittent EFM or one of three different methods of hands-on listening—Doppler ultrasound, Pinard fetal stethoscope used by a research midwife, or Pinard fetal stethoscope used by the attending midwife as was routine in that hospital.

Intermittent EFM was defined as wearing the sensors for the last 10 continuous minutes of every 30 minutes if the results were normal, or the last 10 continuous minutes of every 20 minutes if the results were abnormal. However, the Doppler ultrasound group had the best newborn health outcomes overall. The research midwives in the study used Huntleigh pocket Doppler ultrasound monitors to listen to the fetal heart rate during the last 10 minutes of every half hour, especially before and immediately after a contraction.

The authors concluded that the use of a handheld Doppler device is a more reliable test for abnormal fetal heart rates than intermittent EFM or the use of a Pinard fetal stethoscope. They also note that handheld Dopplers are simple, affordable, and probably cause less discomfort than Pinard fetal stethoscopes. In contrast, it appears that intermittent EFM alone when not combined with other monitoring methods is not based on research evidence. So, some researchers have concluded that it should not be recommended Martis et al.

There is very little research on wireless or mobile continuous electronic fetal monitors. Two small pilot studies in Uganda and the U. Birthing people in these studies reported that they like the mobility that they had with the wireless monitors. Both studies experienced some data loss and delays from wireless connection problems. As we mentioned, there are a variety of devices that can be used for hands-on listening during labor.

Cochrane researchers conducted a review and meta-analysis to find out which types of listening tools and timing protocols are most effective Martis et al. They were only able to find two randomized, controlled trials to contribute data to the meta-analysis.

The studies were conducted in Zimbabwe and Uganda and included a total of 3, participants. When the two studies were combined, they found that a handheld Doppler battery and wind-up is linked to more Cesareans for abnormal fetal heart rate compared to a Pinard fetal stethoscope, but without a clear difference in newborn health outcomes low Apgar scores, newborn seizures, or perinatal death.

However, the quality of the evidence is low and other important newborn health outcomes were not assessed. There is not enough evidence at this time to recommend a Doppler ultrasound or a type of fetal stethoscope as the preferred listening device.

Researchers have looked into the evidence for this practice. They found four studies from the U. Altogether, the studies included more than 13, low-risk participants. The researchers found a tendency towards more Cesareans among the people randomly assigned to EFM on admission compared to those assigned to hands-on listening on admission, but the finding was not statistically significant.

This means that more data is needed before we can detect if there is a real impact of admission EFM on Cesareans. People assigned to EFM on admission were more likely to end up being put on continuous EFM for the rest of their labor.

There were no differences in newborn health outcomes between the groups, including newborn seizures. The authors concluded that there is no evidence of benefit for using EFM on admission in labor among low-risk women, and that hands-on listening is the preferred method. Electronic fetal monitoring usually requires that a mother wear two monitoring belts around her abdomen during labor, which restricts movement and may even require bed rest.

Electronic fetal monitoring also usually means that the mother loses the option of water immersion in a birth pool for pain management. Not all types of continuous EFM restrict mothers from movement. Mobile monitors are designed to free up mothers, but they are not perfect.

Because they are a continuous monitor, they may carry the same increased risk of Cesarean. Another potential downside of EFM is that the sounds or display from the monitor could distract laboring people, leading to an increase in their perceived pain during labor. They found that for some people, watching the monitor made them feel more distracted and stressed, which was linked to feeling more pain during labor.

Laboring people may also feel less supported by their care providers if the providers pay more attention to the monitor than to the person wearing the monitor. Researchers have found that women who do not feel supported by their care providers report more pain and less satisfaction with childbirth Hodnett Perhaps the most important risk of electronic fetal monitors to be aware of is their effect on Cesareans. In the U. Because non-reassuring fetal heart tones can be a vague diagnosis, several professional organizations in the U.

It may be possible to reduce preventable Cesareans from EFM by using scalp stimulation and attempting corrective measures to resolve the concerning fetal heart rate.

However, continuous electronic fetal monitoring generally restricts people to bed-lying positions. Having the mother change positions may be helpful for relieving umbilical cord compression that can cause abnormal fetal heart rate patterns. One of the main reasons EFM is so common is that doctors, nurses, midwives, and hospitals think that it protects them from cerebral palsy lawsuits. However, the introduction of EFM actually had the effect of increasing rates of medical malpractice lawsuits Spector-Bagdady et al.

However, the technology was used against them in court, and trial lawyers for parents were able to win billions in lawsuits against physicians Sartwelle et al. One big reason that EFM dominates labor and delivery units today is that judges and juries decide on whether or not a provider committed medical malpractice based upon something called the standard of care.

Standard of care means, how did this doctor practice compared to how other doctors are currently practicing? Standard of care does not mean best practice, and it also does not necessarily mean evidence-based practice. This catches doctors, nurses, and midwives in a catch the use of EFM is not best practice for many women. The lack of an EFM recording increases the chance that the hospital will lose the lawsuit or have to settle the lawsuit, losing a large amount of money either way Spector-Bagdady et al.

Many hospital labor and delivery units may own only one or two handheld Dopplers—or none at all. Hospital administrators may not understand the value of purchasing small devices for hands-on listening when they have already spent a large amount of money equipping their units with high-tech electronic fetal monitors.

With hands-on listening, the nurse, midwife, or doctor actually has to be at the bedside of the laboring person every minutes during the active phase of the first stage of labor and every minutes during the pushing phase of the second stage of labor. One unexpected benefit of hands-on listening is that it requires caregivers to spend more time with the laboring mother—and their more frequent physical presence may actually lower pain and increase satisfaction for their patients Hodnett Electronic fetal monitoring is big business.

In the early s, there were approximately 28, fetal monitors in more than 3, hospitals in the U. Hospitals spend significantly more on electronic monitoring systems compared to handheld Dopplers.

However, on the other hand, EFM may actually require more time than they realize Smith et al. For example, the time taken to maintain EFM equipment, adjust the monitoring belts, continuously watch the monitor, respond to alarms, and interpret the fetal heart strip, could take longer than the time required to use hands-on listening for minutes every minutes during active labor. In addition, if EFM causes increased maternal discomfort leading to an increased need for pain medication, then this will require increased observation by clinical staff and ultimately a greater strain on human resources.

In the end, using electronic fetal monitoring for everyone is an example of high-tech, high-cost, non-evidence-based care. Most nurses and doctors are not familiar with using a fetal stethoscope and many have little or no training in hands-on listening. I have seen one [fetal stethoscope] in Africa. The device eventually became known as the DeLee-Hillis fetoscope and was at the forefront of intrapartum fetal monitoring for the next half-century.

DeLee himself recommended a program of auscultation every 30 minutes during the first stage of labor, and every three or five minutes, or even continuously during the second stage of labor, when any of described signs of fetal distress were taken as an indication for forceps delivery. Electric, amplified fetoscopes of Matthews, Marvel, and Kirschbaum made the task of fetal monitoring easier by the s when IA became the emerging standard of care. It remained so until well into the s, and is used in some form even today.

However, in , Benson et al. Fetuses were monitored every 15 minutes during the first stage of labor, and every 5 minutes during the second stage of labor. This damning report emerged at a time when true electronic fetal monitoring EFM was being developed and experts were quick to dismiss IA in favor of the hoped-for promise of EFM.

Obstetrics claims to be a scientific profession, one that makes use of research evidence to guide practice. Yet it is easy to see from the history of fetal heart rate monitoring that research evidence had very little to do with the introduction of CTG monitoring. Arney, W. Power and the profession of obstetrics. Hon, E. The electronic evaluation of the fetal heart rate.

American Journal of Obstetrics and Gynecology, 75 6 , Sartwelle, T. Journal of Pediatric Care, 2 2 , Cerebral palsy, cesarean sections, and electronic fetal monitoring: All the light we cannot see.

Clinical Ethics, 45 ,