When you first see your newborn baby, your heart might “skip a beat”. But no one hopes their baby’s heart actually skips a beat. Abnormal heart rates, like fetal bradycardia, can be dangerous.
Here’s what you need to know about how fetal bradycardia occurs, as well as complications that arise when doctors fail to treat it.
What Is Fetal Bradycardia, Sinus Bradycardia & Persistent Fetal Bradycardia?
In simple terms, it’s when an unborn baby’s heart is beating too slowly. It is also known as a low fetal heart rate. Doctors consider a heart rate low if it drops below 110 for longer than 10 minutes or 100 for 5 minutes. These are fetal arrhythmias (as opposed to fetal tachycardia, which is when fetal heart rate stays above 180 BPM).
Sidenote: Premature atrial contractions (PACs) are early heartbeats originating in the atria – the most common form of fetal arrhythmia. Blocked premature atrial contractions are generally benign, but
A normal fetal heart rate is generally between 110-160 beats per minute. Persistent fetal bradycardia is simply when it persists. There are four types of bradycardia:
Sinus Bradycardia. Fetal sinus bradycardia in an infant is when the child has a slower-than-normal heart rate for a baby, and the rhythm of the heart originates from the sinus node. For babies, this is usually defined as a heart rate lower than the 5th percentile for age. Transient sinus bradycardia occurs when the fetal heart rate drops into the bradycardia range, but then returns to normal.
First Degree: Atrioventricular (AV) Block. A first-degree AV block is a mild heart rhythm issue. It slows down the electrical signals traveling through the heart (from atria to ventricles) but doesn’t stop them. This doesn’t typically need treatment.
Second Degree: Partial Heart Block. When those electrical signals traveling through the heart are intermittently blocked and don’t reach the lower chambers, this is a partial heart block. This heart block causes a dropped (or missed) beat. This is more serious and medical professionals may consider various treatments depending on the details.
Third Degree: Complete Heart Block. When the electrical signals from the heart’s top chambers are fully blocked and can’t reach the lower chambers, this is a complete heart block. This congenital heart block is very serious, as it causes the heart to beat much slower than normal.
The diagnosis of fetal bradycardia doesn’t always indicate a problem. Sometimes it’s a normal variation and resolves by itself. But it can also be a clear sign that something is wrong with the fetus. It could mean the brain isn’t getting enough blood or oxygen.
That’s a dangerous and worrisome situation. Just a few minutes without oxygen can cause permanent damage to a baby’s brain. For this reason, doctors must monitor fetal heart rate during labor and delivery. If it occurs, the next step is to determine what’s causing it.
Various Causes
A variety of factors can make a baby’s heart rate slow down, including:
- A reflex triggered by a medical procedure called umbilical cord sampling.
- A problem with the heart’s electrical system (conduction abnormality).
- A reflex triggered by pressure on the baby’s head or the umbilical cord.
- When the mother exercises too much (this can affect her oxygen levels).
- Low oxygen levels due to the baby’s heart pumping weakly.
- When certain receptors in the baby’s blood vessels sense pressure.
But let’s get a little more specific and delve into the common causes.
Common fetal bradycardia causes include:
- Maternal medication. Certain medications, such as beta-blockers, can cross the placenta. They can reach the fetus and affect its heart rate. Epidural anesthesia and certain medications used to induce or augment labor can lead to bradycardia as well.
- Maternal hypotension. A decrease in the mother’s blood pressure can lead to a decrease in blood flow to the placenta.
- Fetal heart failure or abnormalities. Structural heart disease problems like congenital heart defects can cause it as well.
- Fetal infections. Certain infections can affect the fetal heart rate. Examples include cytomegalovirus (CMV) and parvovirus B19.
- Uterine rupture. A ruptured uterus can cause fetal distress and lead to bradycardia in a baby.
- Systemic lupus erythematosus in the mother. This autoimmune disease can slow the fetal heart rate through the development of congenital heart block in the fetus.
- Cord compression. Compression of the umbilical cord can reduce blood flow to the fetus and slow the heartbeat.
- Polyhydramnios or Oligohydramnios. These terms refer to too much or too little amniotic fluid in the womb.
How should doctors manage bradycardia in a baby? That will vary depending on when bradycardia is taking place and how severe it is. Treatment during pregnancy may be different from treatment during labor. Often, management includes treatment for fetal bradycardia causes. For example, if maternal hypotension is the cause, doctors should work to raise the mother’s blood pressure.
Fetal Distress Complications & Prognosis Of Bradycardia in a Baby
What happens when doctors fail to catch or treat the condition? Distress, complications and injuries can result.
The prognosis for a fetus is much better when doctors act fast to respond to it.
Otherwise, a fetus could suffer a temporary or permanent injury, such as:
- Complete or partial oxygen deprivation
- Stillbirth
- Preterm birth
- Brain damage.
- Paralysis
- Long-term developmental delays
- Nerve damage
- Organ damage
- Cerebral palsy
At times, these injuries occur because of a doctor’s negligence.
Here are some ways that might happen:
- Failing to monitor heart rate
- Failing to detect fetal bradycardia causes and treat them.
- A defective monitoring device, or improper installation.
- Failing to deliver a baby by C-section when bradycardia shows it’s necessary.
Let’s say a doctor is negligent while handling the condition, leading to complications. The child’s parents could have grounds to file a malpractice lawsuit.
Here’s an example: A monitor detects a severely low fetal heart rate during delivery. The mother has been in labor for over 7 hours. The issue with the baby’s heart rate is severe enough to require an emergency C-section. But the doctor in charge doesn’t order one.
Instead, the birth team attempts to extract the baby with a vacuum. The bradycardia gets worse, so the doctor finally orders a C-section. But it’s too late. The baby is stillborn. The parents file suit against the doctor and birth team for their negligence. The case settles for $1 million.
Get Legal Help For Birth Injuries
Nothing can take away the pain a parent feels after losing a child. But a successful birth injury lawsuit can help prevent a doctor from continuing to commit malpractice. It can also provide a way to pay medical bills when a child must grow up with a permanent injury. Birth injury cases stemming from fetal bradycardia can settle for thousands if not millions of dollars.
It’s important to take legal action right away. The statute of limitations prevents you from filing a lawsuit after a certain number of years have passed. It varies by state.
Contact our birth injury lawyers today to find out if you have a case.
Fetal Bradycardia FAQs
Bradycardia in a fetus can be caused by several factors, including umbilical cord compression, fetal hypoxia, maternal drug use, congenital heart defects, or prolonged maternal hypotension.
Fetal bradycardia can be an emergency if the heart rate is significantly low for extended periods, as it may indicate distress and the potential for harm to the fetus.
The duration of fetal bradycardia can vary. Short episodes may be benign, especially if they occur during uterine contractions. Persistent or severe bradycardia may require immediate medical evaluation and intervention.
Fetal bradycardia can be very concerning, but the good news is, it doesn’t always mean the baby won’t survive. In fact, it’s often harmless and goes away relatively quickly. It’s the severe cases and cases involving severe negligence that can be fatal. However, with appropriate and timely medical intervention, many babies can survive and go on to be healthy.
