Fetal Distress: Symptoms, Types, Causes and Treatment

Fetal distress is a critical condition during pregnancy or labor that signals the baby is not well, often due to a lack of oxygen (hypoxia) or other complications. Recognizing and responding to fetal distress can make a significant difference in both immediate and long-term outcomes for both the baby and parents. In this article, we'll explore the symptoms, types, causes, and treatment options for fetal distress, synthesizing the latest research for a clear, human-centered understanding.

Symptoms of Fetal Distress

Fetal distress doesn't always present in obvious ways, but there are key symptoms that alert clinicians and parents that something may be wrong. Rapid identification and interpretation of these signs are essential for the best possible outcome.

Symptom	Description	Detection Method	Source(s)
Abnormal Heart Rate	Deviations from normal fetal heart rate patterns	Cardiotocography, monitoring	6 8 11 15
Decreased Movement	Reduced fetal movement or activity	Maternal perception, ultrasound	8
Late Decelerations	Heart rate dips after contractions	Fetal heart monitoring	2 11
Meconium-Stained Fluid	Presence of meconium in amniotic fluid	Visual examination during labor	14

Table 1: Key Symptoms of Fetal Distress

Understanding Key Symptoms

Abnormal Heart Rate Patterns

The most widely recognized sign of fetal distress is an abnormal fetal heart rate (FHR). These patterns can include tachycardia (fast heart rate), bradycardia (slow heart rate), or variable/late decelerations. Continuous monitoring, often via cardiotocography (CTG), is standard practice in many labor and delivery settings 6 8 11 15.

Decreased Fetal Movement

A noticeable reduction in fetal movement, especially in the third trimester or during prolonged pregnancy, can indicate fetal compromise. This symptom is often first detected by the mother and should prompt further evaluation 8.

Late Decelerations

Late decelerations refer to a drop in the fetal heart rate that begins after a uterine contraction has started and recovers after the contraction ends. This is often a sign of inadequate oxygen transfer to the fetus and is particularly concerning in the setting of labor 2 11.

Meconium-Stained Amniotic Fluid

When meconium (the baby's first stool) is present in the amniotic fluid before birth, it can be a sign of fetal distress and may increase the risk of complications for the baby 14.

Types of Fetal Distress

Fetal distress is not a one-size-fits-all diagnosis. It can present in different forms, each carrying different risks and requiring tailored management.

Type	Typical Scenario	Features	Source(s)
Acute Distress	Sudden, severe compromise (often in labor)	Rapid onset, abnormal FHR	11 12 15
Chronic Distress	Gradual compromise (often antepartum)	Growth restriction, oligohydramnios, mild FHR changes	8
Hypoxic Distress	Caused by reduced oxygen supply	Acidosis, abnormal FHR, decreased movement	6 9

Table 2: Types of Fetal Distress

Acute vs. Chronic Distress

Acute Fetal Distress

• Definition: Rapid onset of fetal compromise, typically during labor.
• Features: Severe bradycardia or other abnormal FHR patterns, often requiring urgent intervention.
• Examples: Umbilical cord prolapse, placental abruption, or acute maternal hypotension 11 12 15.
• Management: Immediate resuscitative efforts, often leading to expedited delivery.

Chronic Fetal Distress

• Definition: Gradual deterioration of fetal well-being, often identified before labor.
• Features: Evidence of intrauterine growth restriction (IUGR), oligohydramnios (low amniotic fluid), and subtle changes in fetal behavior or heart rate 8.
• Examples: Prolonged pregnancy with oligohydramnios leading to umbilical cord compression 8.
• Management: Close monitoring, planned delivery if risk escalates.

Hypoxic Distress

This term specifically refers to fetal distress caused by inadequate oxygenation. Hypoxia can be acute or chronic and is often detected by the combination of abnormal FHR patterns and laboratory evidence of acidosis 6 9.

Causes of Fetal Distress

Understanding the root causes of fetal distress is crucial for prevention, early recognition, and effective intervention. Causes span physiological, mechanical, and even psychological domains.

Cause	Mechanism	Example/Notes	Source(s)
Umbilical Cord Compression	Reduced blood flow to fetus	Oligohydramnios, cord prolapse	8 11
Uteroplacental Insufficiency	Poor oxygen/nutrient transfer	Hypertension, diabetes	8 9
Maternal Infection/Inflammation	Placental damage or dysfunction	SARS-CoV-2, chorioamnionitis	5
Fetal Anomaly	Structural or functional abnormality	CHD, hydrothorax, volvulus	2 3 4 10 15
Oxidative Stress	Accumulation of reactive oxygen species	Hypoxic injury to tissues	9
Prolonged Labor/Contractions	Reduced oxygenation during contractions	Hyperstimulation	11 12
Maternal Stress	Neuroendocrine changes affecting fetus	High CRH/cortisol levels	7

Table 3: Main Causes of Fetal Distress

Mechanical and Physiological Causes

Umbilical Cord Compression

This is a leading cause of acute fetal distress, particularly in cases of oligohydramnios (low amniotic fluid) or cord prolapse. Compression impedes blood flow between the placenta and fetus, leading to hypoxia 8 11.

Uteroplacental Insufficiency

Conditions such as hypertension, diabetes, or advanced maternal age can compromise the placenta's ability to deliver oxygen and nutrients, resulting in fetal hypoxia and growth restriction 8 9.

Maternal Infection or Inflammation

Infections like SARS-CoV-2 can cause placental inflammation, reducing the maternal-fetal interface and leading to fetal distress and even neonatal multi-organ failure 5.

Fetal Anomalies and Other Complications

• Congenital anomalies such as congenital heart disease (CHD), hydrothorax, or intestinal volvulus can directly impair fetal oxygenation or circulation, presenting as distress 2 3 4 10 15.
• Oxidative stress in the fetal and maternal blood, marked by increased superoxide and reduced catalase activity, is linked to hypoxia and tissue injury 9.

Other Contributing Factors

Prolonged or Hyperstimulated Labor

Frequent or intense contractions can compromise fetal oxygenation, especially if the fetus is already at risk 11 12.

Maternal Stress

Chronic psychological stress in the mother results in elevated stress hormones (CRH, cortisol) that can affect fetal development, lower birth weight, and increase the risk of distress 7. There is also emerging evidence of psychological distress in parents following poor fetal outcomes, which may influence care and mental health 1 3 4 10.

Treatment of Fetal Distress

Timely and appropriate intervention is vital to reverse or minimize harm from fetal distress. Management strategies are chosen based on the underlying cause, the severity of symptoms, and the stage of pregnancy or labor.

Treatment	Purpose/Action	Context	Source(s)
Intrauterine Resuscitation	Improve fetal oxygenation	Acute distress during labor	11 12
Maternal Oxygen Administration	Increase maternal-fetal oxygen transfer	Widely used, evidence limited	13
Expedited Delivery	Rapidly deliver compromised fetus	Severe or persistent distress	14 15
Decompression Procedures	Relieve mechanical compression	Fetal hydrothorax, volvulus	2 15
Beta-agonist Medications	Reduce uterine contractions	Temporizing measure	12
Multidisciplinary Support	Address mental health and psychosocial needs	Parents of at-risk fetuses	1 3 4 10

Table 4: Main Treatments for Fetal Distress

Immediate Interventions

Intrauterine Resuscitation

A set of urgent measures to improve fetal oxygenation, including:

• Repositioning the mother (left lateral, knee-elbow, etc.)
• Rapid IV fluids
• High-concentration oxygen for the mother
• Reducing or stopping uterine contractions (with medications like terbutaline or beta-agonists)
• Intra-amniotic infusion, especially in cases of oligohydramnios 11 12

Maternal Oxygen Administration

While commonly used, the evidence for maternal oxygen therapy is mixed. There is insufficient data to support routine use, and prolonged oxygen administration may even lower umbilical artery pH, potentially worsening outcomes 13.

Delivery and Specialized Procedures

Expedited Delivery

If resuscitation fails or distress persists, rapid delivery—either by cesarean section or operative vaginal birth—is usually indicated to prevent further harm 14 15.

In-Utero Decompression

For mechanical causes of distress (e.g., hydrothorax or volvulus), emergency fetal procedures such as thoracocentesis or placement of drainage catheters can reverse distress and buy time for safer delivery 2 15.

Beta-agonist Medications

Short-acting beta2 agonists such as terbutaline or hexoprenaline can temporarily reduce uterine contractions, improving placental blood flow and fetal oxygenation as a bridge to further intervention 12.

Multidisciplinary and Psychosocial Support

Fetal distress often has profound psychological effects on parents. Multidisciplinary teams—including mental health professionals—can provide trauma-informed care, psychological screening, and targeted interventions to support families through and after complicated pregnancies 1 3 4 10.

Conclusion

Fetal distress is a complex syndrome with varied presentations, causes, and management strategies. Early recognition and a tailored response can dramatically improve outcomes for both babies and families. The emotional impact on parents is significant and should not be overlooked in comprehensive care.

Key points:

• Abnormal fetal heart rate patterns, decreased movement, and meconium-stained fluid are core symptoms of fetal distress.
• Fetal distress can be acute or chronic, with hypoxia being a common underlying factor.
• Causes are diverse: umbilical cord issues, placental insufficiency, infections, anomalies, oxidative and maternal stress, and labor complications.
• Treatment may involve intrauterine resuscitation, maternal oxygen, expedited delivery, emergency fetal procedures, and comprehensive psychosocial support.
• Multidisciplinary care—addressing both medical and emotional needs—is vital for the well-being of the fetus and the family.

Awareness, rapid action, and holistic support are the cornerstones of managing fetal distress effectively.