Half a century ago, continuous fetal heart rate monitoring became the norm with the hope it would improve neonatal outcomes. At the time, we were not sure of the causes behind many cases of cerebral palsy, intellectual disability, and more.
Professionals believed hypoxia, or lack of oxygen, during birth caused poor neonatal outcomes. Making continuous fetal heart rate monitoring standard care, providers hoped to improve outcomes. It made sense, keeping an eye on fetal heart rate. Much of medicine is simply trying new things and observing the results.
Decades later, that has not proven to occur. Continuous FHR monitoring for all does not improve neonatal outcomes. It is, however, associated with an increased risk of c-section birth. What do you need to know as a doula? Read on to learn more.
How Does Continuous Fetal Heart Rate Monitoring Increase C-Sections?
As doulas, it is important to understand that there is a role for FHR monitoring, whether intermittent or continuous. There are specific circumstances where continuous monitoring is safest for baby.
However, what evidence shows for the general population is that continuous FHR monitoring increases the risk of c-section without decreasing poor neonatal outcomes on a population level.
“Only two randomised trials, both published more than 25 years ago, have compared cerebral palsy rates in births monitored electronically or by intermittent auscultation. Cerebral palsy cannot be diagnosed at birth, so infants have to be followed for several years, until a diagnosis can reliably be made. In a trial in 13 079 births in Dublin, evaluation at age 4 years indicated that the rate of cerebral palsy was not lower in children whose births were monitored electronically. A multicentre randomised trial in the US compared 93 singleton, vertex presenting infants with birth weight ≤1750 g whose births were monitored electronically with 96 comparable children monitored by intermittent auscultation. At 18 months of age, the cerebral palsy rate was significantly higher in the electronically monitored group.”
You can read the full publication on the NIH website, published in 2016. Meaning, we have had evidence for years showing fetal monitoring does not necessarily reduce the rate of cerebral palsy. This was one of the main reasons for the initial development and push for continuous monitoring.
So, what does that have to do with the increased risk of c-section? Well, the variations in heart tones picked up in continuous monitoring can lead to c-sections for fear of fetal distress. True fetal distress does occur. However, normal, temporary, variations in fetal heart tones can show up. This leads to misinterpretation for true fetal distress.
With intermittent monitoring, along with looking at the overall picture of the birther and baby, can reduce c-section rates without increasing poor neonatal outcomes. It is important for providers to begin following evidenced-based information. New guidelines aim to support that.
Do Fetal Heart Rate Variations Always Mean Fetal Distress?
The study mentioned above also states:
“Use of electronic fetal monitoring to prevent cerebral palsy was based on several erroneous assumptions. Firstly, fetal heart rate decelerations are commonly associated with peripheral chemoreflex rather than compression of the fetal head or umbilical cord and may be relatively unthreatening. Furthermore, studies consistently show that most cases of cerebral palsy in babies born at or near term are not caused by birth asphyxia but associated with congenital malformations, fetal growth restriction, intrauterine exposure to infection or inflammation, and other unknown factors.”
Simply put, we are still learning:
- To properly interpret fetal heart tones
- About the cause of poor neonatal outcomes in near or at term babies
- And what all this means in terms of clinical practice
What Are Current Recommendations?
Many birthing facilities have varying policies in terms of continuous fetal monitoring or intermittent fetal monitoring. These policies can vary quite significantly.
However, a new 2022 publication in the Journal of Obstetrics and Gynecology summarizes a new recommendation saying in brief:
“Evidence-based medicine should replace tradition in the use of electronic fetal heart rate monitoring.”
Continuous fetal monitoring use had good intentions. Unfortunately, continuous fetal monitoring showed little benefit across the board. However, tradition remained over evidenced based policy.
In more detail, the journal states the following:
“…after a half century of use and millions of cesarean deliveries based on FHR monitoring, evidence for such improvement remains absent. This dichotomy appears to be related to widespread misconceptions regarding the physiology underlying various FHR patterns and the developmental origins of cerebral palsy. These misconceptions are strengthened by a reliance on anecdotal experience and tradition in lieu of evidence-based medicine, the confusing “category II” FHR designation, medical-legal considerations, and our tendency to view fetal monitoring, as originally conceptualized, as a single, indivisible entity whose concepts must be accepted or rejected en bloc. Ill-defined and largely imaginary conditions such as “depletion of fetal reserve” are particularly harmful and their use in clinical medicine uniquely not evidence based.”
What Does This Mean For Doulas?
As doulas, many of us have long been aware of the risks of continuous fetal monitoring for all births. This means more than just one’s with medical necessity.
There is evidence to support the use of continuous FHR monitoring when baby is at risk of fetal distress. Some examples of that include due to prematurity, congenital birth defect, or the need for Pitocin.
However, for typical birth situations, especially unmedicated ones, continuous fetal monitoring can:
- Increase the risk of c-section
- Discomfort increase
- Limit mobility which can potentially prolong labor
- Increase stress for parents listening to normal heart tone variations
During prenatal meetings with clients, it can be helpful to educate them about birth options. Encourage them to have conversations with their providers about continuous versus intermittent monitoring. Doulas need to take time to provide clients with many resources. Point them to evidenced based resources so they can make informed decisions about their care. Finally, support them in whichever decision they make.