A prolapsed cord, or umbilical cord prolapse, happens when the umbilical cord slips ahead of or alongside the baby during labor, typically after the membranes rupture (when your water breaks). It occurs in roughly 1 to 2 out of every 1,000 births and is considered an obstetric emergency because the cord can become compressed between the baby and the birth canal, cutting off the baby’s oxygen supply.
How a Prolapsed Cord Happens
During a normal delivery, the baby’s head (or bottom, in a breech birth) sits snugly against the cervix, keeping the umbilical cord safely behind. A prolapse occurs when something creates a gap between the baby and the cervix, allowing the cord to slip through first. Once the cord is below the baby, each contraction can squeeze it against the walls of the birth canal or against the baby’s body, reducing or stopping blood flow. That blood carries all the oxygen the baby receives, so even brief compression can cause the baby’s heart rate to drop sharply.
There are two types. In an overt prolapse, the cord drops visibly into or through the vagina. A healthcare provider can feel a pulsating cord during a vaginal exam, and in some cases the mother herself can see or feel it. In an occult prolapse, the cord slips alongside the baby but stays hidden inside. It’s not visible or palpable, so the only clue is a sudden change in the baby’s heart rate on the monitor.
Who Is Most at Risk
A large population-based study of over 10 million births found that the strongest risk factors were early gestational age (premature babies are smaller, leaving more room for the cord to slip past), breech or other abnormal positioning, grand multiparity (having had many previous births), and prolonged labor. In breech presentations specifically, the incidence rises to slightly above 1%. Excess amniotic fluid also plays a role because when membranes rupture, the sudden rush of fluid can carry the cord downward.
Perhaps surprisingly, the same study found that most cases actually occur in low-risk women delivering at full term. Having no risk factors does not eliminate the possibility.
Medical Procedures That Can Trigger It
Up to half of all cord prolapses are iatrogenic, meaning they’re caused by a medical procedure performed during labor. The most common culprit is amniotomy, the artificial breaking of the membranes, particularly when the baby’s head hasn’t yet settled deep into the pelvis. Other procedures linked to prolapse include external cephalic version (manually turning a breech baby from outside the abdomen), placement of a cervical ripening balloon, insertion of internal fetal monitors, and manual rotation of the baby’s head during labor.
Because of this risk, clinical guidelines recommend postponing amniotomy when the baby’s head is high and not firmly engaged against the cervix. When these procedures are necessary, providers take extra care to minimize the chance of displacing the baby’s head upward and creating space for the cord.
What It Feels or Looks Like
In many cases, there are no symptoms the mother can detect on her own. The first sign is often a sudden drop in the baby’s heart rate on the electronic fetal monitor, especially right after the membranes rupture. Heart rate monitoring typically shows either a sustained slow heart rate (bradycardia) or repeated sharp dips called variable decelerations. These patterns appear in about two-thirds of overt prolapse cases.
In some situations, though, the signs are more obvious. You might feel something unfamiliar in your vagina after your water breaks, or see a loop of cord protruding. If that happens, it’s critical to get into a hands-and-knees position (with your chest low and hips raised) and call for emergency help immediately. This position uses gravity to shift the baby’s weight off the cord.
How It’s Managed
Once a prolapse is identified, the goal is to relieve pressure on the cord and deliver the baby as quickly as possible. A provider will typically place a gloved hand inside the vagina to physically lift the baby’s presenting part (usually the head) off the cord, holding it there continuously until delivery. At the same time, the mother is positioned to reduce compression, often in a knee-chest position or with the bed tilted so her head is lower than her hips.
In most cases, this means an emergency cesarean section. Speed matters enormously. If the mother is already fully dilated and the baby is low enough, an assisted vaginal delivery with forceps or vacuum may be faster. The population study found that vaginal delivery, when it was achievable, carried a lower risk of fetal injury than cesarean (8.7% versus 18.5%), likely because it avoided the additional time and surgical manipulation involved in a cesarean.
Risks to the Baby
The central danger is oxygen deprivation. When the cord is compressed, the baby’s blood oxygen drops, and the heart rate slows. If compression is brief and delivery is fast, most babies do well. Prolonged compression, however, can lead to lower Apgar scores (the standard assessment of a newborn’s condition), a need for assisted ventilation at birth, neonatal seizures, and in severe cases, long-term brain injury.
The population study confirmed that cord prolapse is associated with higher rates of low Apgar scores, breathing difficulties, seizures, and fetal injuries compared to deliveries without prolapse. Outcomes depend heavily on how quickly the prolapse is recognized and how fast the baby can be delivered. In hospitals with operating rooms immediately available, the prognosis is generally good. The risk increases significantly for out-of-hospital births or in facilities where surgical delivery requires transfer to another location.
Can It Be Prevented?
There is no reliable way to prevent cord prolapse entirely, but the prevalence may be slowly declining thanks to increased use of third-trimester ultrasound, which can identify risk factors like abnormal fetal positioning or a low-lying cord before labor begins. When providers know a patient is at elevated risk, they can plan accordingly: avoiding unnecessary amniotomy, ensuring the baby’s head is well engaged before breaking membranes, and having the labor take place in a facility equipped for rapid cesarean delivery.
For the roughly half of cases that happen spontaneously in low-risk pregnancies, the best protection is continuous fetal heart rate monitoring during labor. This allows the care team to detect the sudden heart rate changes that signal cord compression and act within minutes.