What Causes Variable Decelerations?

Variable decelerations are typically caused by umbilical cord compression during labor, which reduces blood flow and leads to sudden drops in a baby’s heart rate. In some cases, the compression resolves once the baby shifts position. If the decelerations keep happening or worsen over time, however, it can signal that the baby is in distress and needs intervention.

Understanding what causes variable decelerations can help you make sense of what happened during your delivery and if the medical team responded appropriately. If you suspect an error was made, a birth injury lawyer can review your case and help you pursue a medical malpractice lawsuit if the care you and your child received did not meet accepted standards.

What Are Variable Decelerations?

Variable decelerations are sudden drops in a baby’s heart rate during labor, usually falling at least 15 beats per minute for 15 seconds or more. These drops can happen during contractions or between them, and can look different from one contraction to the next.

Providers will often describe variable decelerations as:

• Intermittent: Meaning they occur with fewer than half of the contractions in a 20-minute period.
• Recurrent: Meaning they appear with at least half of the contractions in that same timeframe.

Recurrent variable decelerations tend to get more attention because they can signal that your baby needs closer monitoring or additional support during labor.

How Umbilical Cord Issues Can Trigger Variable Decelerations

Most variable decelerations happen because the umbilical cord is being compressed. When the cord is squeezed, even briefly, it can interrupt blood flow and oxygen delivery to the baby, leading to a sudden drop in heart rate.

Several situations during labor can create or worsen cord compression:

• Low amniotic fluid: When there is less fluid around the baby, the umbilical cord doesn’t have as much cushion. This makes it easier for the cord to become pinched during contractions.
• After the water breaks: Once the membranes rupture, the space around the cord can shift. Some babies experience more variable decelerations after the water breaks because the cord is less protected.
• Cord position issues: A cord wrapped around the neck (nuchal cord), around the baby’s body, or positioned between the baby and the uterine wall can lead to periodic compression as the baby moves down during labor.
• Cord prolapse or severe compression: In more urgent cases, the cord may slip in front of the baby or become tightly compressed. This can quickly reduce oxygen delivery and requires immediate medical action.
• Baby’s position during labor: As the baby rotates and descends, strong contractions or a particular position may briefly compress the cord and trigger variable decelerations.

If there were variable decels during your labor, an umbilical cord birth injury lawyer can help you understand what the monitoring showed and if there was medical negligence during childbirth. 

Are Variable Decelerations Always a Sign of Fetal Distress?

While it can be stressful and worrying to see variable decelerations on a fetal heart monitor, they are not always a sign that a baby is in serious trouble. 

It’s actually common for babies to experience occasional variable decelerations during labor, especially during strong contractions, but they typically recover quickly. When the overall heart rate looks healthy, these brief dips are generally considered manageable.

When Do Variable Decelerations Require Closer Attention?

Variable decelerations become more concerning when the pattern suggests the baby may be struggling to maintain oxygen levels. Specifically, providers tend to view variable decelerations as concerning when they are:

• Recurrent: Appearing with at least half of the contractions in a 20-minute period. This can signal repeated cord compression.
• Deep or prolonged: Dropping sharply or taking longer to recover, especially when paired with a slow return to baseline.
• Accompanied by other changes: This can include decreased variability or an increasing baseline heart rate, which can suggest the baby is working harder to compensate.

In these situations, the medical team should respond quickly with appropriate interventions, such as repositioning the parent, giving fluids, adjusting Pitocin, or preparing for operative delivery if the tracing continues to decline.

When Can Variable Decelerations Be Connected to a Birth Injury?

The thing to pay attention to in these cases is not the presence of a single deceleration, but how or if the medical team evaluated and responded to any potential ongoing pattern of decelerations. 

In other words, did the medical team follow accepted standards of care, and did they act in time to protect the baby? 

To determine whether a birth injury took place, your lawyer will look at:

• The fetal heart rate and whether it was interpreted correctly in accordance with standard definitions and clinical guidelines.
• If any worsening or recurrent patterns were taken seriously and escalated appropriately.
• Whether reasonable interventions were attempted promptly, such as repositioning, stopping labor-stimulating medications, or starting oxygen support.
• If the delivery occurred soon enough after fetal distress became evident and conservative measures were not working.

If a baby experiences prolonged oxygen deprivation and the response is delayed, the risk of conditions such as Hypoxic Ischemic Encephalopathy (HIE), brain injury, or long-term neurological damage increases.

A birth injury lawyer can work with medical experts to evaluate your records and help you gather evidence to file an umbilical cord birth injury claim if medical negligence occurred.  

Did a Medical Error Cause Variable Decelerations During Your Labor and Delivery? We Can Help.

Birth Injury Lawyers Group was founded in 2003 by an attorney whose own children faced complications at birth, and that experience continues to guide the work we do for families today. Our team has recovered over $750 million in medical negligence settlements, helping parents get the support they need after a birth injury.

If you have questions about variable decelerations and how they could relate to a possible birth injury, you can contact Birth Injury Lawyers Group for a free case evaluation.