The Safety of Intermittent Auscultation in Labor

The Midwives of NJ are committed to providing safe, evidence-based care that supports natural childbirth. Heart rate monitoring is a crucial part of ensuring the baby’s well-being during labor. Intermittent auscultation (IA) is a safe and effective way to monitor baby’s heart rate during labor in low-risk pregnancies. IA involves using a hand-held Doppler ultrasound device to listen to the baby’s heart rate every so often, rather than using continuous electronic monitoring.

Types of Monitoring: Intermittent Auscultation vs. Continuous Monitoring

There are different types of monitoring for tracking a baby’s heart rate during labor. While continuous electronic fetal monitoring (EFM) is commonly used, it continuously records the heartbeat and uterine contractions, often leading to more medical interventions. Intermittent auscultation provides a safe alternative for low-risk pregnancies, reducing unnecessary interventions while allowing for a more natural labor process.

Advantages of Intermittent Auscultation:

• Fewer Medical Interventions: IA is associated with lower rates of cesarean sections, forceps deliveries, and epidural use. Continuous monitoring, particularly internal monitoring, may involve attaching a sensor to the baby’s scalp to track the heartbeat, sometimes leading to unnecessary interventions (Source).
• More Freedom to Move: Unlike continuous monitoring, which requires women to stay in bed, IA allows movement, making labor more comfortable and even helping contractions progress naturally (Source).
• Better Birth Experience: Women using IA often feel more in control and connected to their labor rather than being restricted by machines.
• Less Stress and Anxiety: Continuous monitoring can produce false alarms, leading to unnecessary interventions and added stress for the mother and care team (Source)

Intermittent Auscultation is Safe & Evidence-Based

Research has consistently shown that IA is a safe and effective method for monitoring low-risk pregnancies. Studies suggest that it is associated with lower rates of cesarean sections and instrumental births compared to continuous EFM, without increasing the risk of poor neonatal outcomes.

Several studies have examined the result of intermittent auscultation versus continuous electronic fetal monitoring on delivery methods and neonatal outcomes:

• Intrapartum Admission Cardiotocography Study (2006): This meta-analysis evaluated the use of admission cardiotocography (a form of continuous EFM) in low-risk pregnancies. The findings indicated that continuous monitoring increased the rates of cesarean sections and instrumental deliveries without significant improvement in neonatal Apgar scores at 5 minutes (Source)
• Effectiveness of Intrapartum Fetal Surveillance Study (2021): This comprehensive analysis compared various fetal monitoring methods, including IA and continuous EFM. The study concluded that IA was associated with a reduced risk of emergency cesarean deliveries compared to continuous EFM, without an increase in adverse neonatal outcomes (Source)  
• Continuous Electronic Fetal Monitoring Study (2024): Research published in Frontiers in Global Women’s Health found that continuous EFM was linked to higher rates of instrumental-assisted vaginal deliveries and cesarean sections due to concerning fetal heart rate patterns, compared to IA. Importantly, there were no significant differences in immediate neonatal outcomes between the two groups (Source)

Intermittent Auscultation is Safe and Supported by Experts

Research confirms that IA is a safe and effective method of fetal monitoring for low-risk pregnancies. Organizations such as the American College of Nurse-Midwives (ACNM) and the Association of Women’s Health, Obstetric and Neonatal Nurses (AWHONN) support IA as a standard of care. These organizations emphasize that IA promotes physiologic birth while reducing the risk of unnecessary interventions associated with continuous monitoring.

American College of Obstetricians Supports IA to Reduce Cesarean Rates

The American College of Obstetricians and Gynecologists (ACOG) recommends intermittent auscultation as a key strategy to lower the primary cesarean rate in low-risk pregnancies.

Research shows that routine use of continuous monitoring increases the likelihood of unnecessary cesarean sections without improving birth outcomes. In the U.S., “non-reassuring fetal heart tones” account for 23% of first-time cesarean deliveries, making it the second most common reason after “failure to progress” (34%) (Source).

Using IA instead of continuous external monitoring can reduce false-positive readings of fetal distress and avoid unnecessary surgical births. Lowering the primary cesarean rate is important for long-term maternal health because cesareans increase the risk of complications in future pregnancies.

Where is Intermittent Auscultation Used?

Intermittent auscultation (IA) is a widely accepted method for monitoring fetal heart rate during labor, especially in low-risk pregnancies. However, the likelihood of IA being utilized can vary depending on the birth setting and birth provider.

• Birth Centers: Often the preferred option for low-risk pregnancies, as they prioritize natural birth.
• Home Births: Commonly used in planned home births, supporting a more personalized and less invasive approach.
• Hospitals: While IA is recommended for healthy, low-risk women, many hospitals still rely ENTIRELY on continuous external monitoring, which can increase medical interventions without improving outcomes.

When Continuous Monitoring Might Be Needed:

Continuous monitoring is recommended if:

• You are considered high-risk and have health issues like high blood pressure or diabetes.
• Labor is being induced or strengthened with medications.
• There are concerns about your baby’s health, such as abnormal heart rate patterns or other complications.
• You have an epidural
• If the fetal heart rate by Intermittent Auscultation is abnormal in some way so continuous monitoring is required to more closely monitor the baby’s status

Long-Term Considerations

For low-risk pregnancies, IA provides long-term benefits by reducing unnecessary cesareans and interventions that could impact future births. Avoiding excessive interventions during labor supports better maternal health and improves the chances of natural births in future pregnancies.

Summary

Intermittent auscultation is a vital part of midwifery-led care, balancing safety with a woman-centered approach to childbirth. By using effective heart rate monitoring while allowing uterine contractions to progress naturally, IA remains a preferred method of fetal monitoring for low-risk pregnancies, supporting safer, more peaceful & positive birth experiences.