Short Umbilical Cord Causes and Long Term Effects

The umbilical cord is the tube that connects the baby to the placenta during pregnancy (1). The cord is made up of three vessels: two arteries that carry waste from the baby back to the placenta to be removed, and one vein that carries nutrients and oxygen from the placenta to the baby.

Normally, umbilical cords are between 55 and 60 cm long. An umbilical cord is considered short if it measures under 35 cm in length (2). Usually, when a baby moves around, the tension on the cord promotes growth and development, lengthening the cord to cater to this growth as the pregnancy progresses. If the cord is too short, it means that the baby might not be moving and growing enough, signaling a potential health issue. Short cords can also pose a risk for numerous delivery complications and birth injuries. Short umbilical cords appear in roughly 6% of deliveries (3).

Your doctor can make detailed evaluations of the cord using ultrasound. If there is an issue, it is important that they closely monitor the mother and child using prenatal tests. Sometimes it is necessary to admit the mother for continuous monitoring for optimal health outcomes.

The most severe complication of a short umbilical cord is placental abruption, a condition in which the mother’s placenta pulls away from the uterus, resulting in severe, life-threatening maternal bleeding. This usually requires an emergency C-section to prevent the child from experiencing dangerous oxygen deprivation and sustaining permanent brain damage.

An umbilical cord is considered short if it is less than 35 cm at term, although some researchers and clinicians consider 40 cm or even 45 cm to be short.

These issues can lead to complications for the baby, including (2):

• Hypoxic-ischemic encephalopathy (HIE)
• Cerebral palsy
• Umbilical cord rupture
• Breech presentation
• Miscarriage/stillbirth
• Intrauterine growth restriction (IUGR)
• Placental disruption (difficulty transferring nutrients from the placenta to the baby)

These issues can lead to complications for the baby, including (2):

• Placental abruption
• Inversion of the uterus
• Prolonged labor
• Retained placenta
• Hemorrhage (caused by placental abruption)

Umbilical cord length is, in part, determined by hereditary factors. Listed below are other factors associated with a short umbilical cord (2):

• A woman who is of average weight or less (normal or below normal body surface area)
• A woman who is pregnant for the first time
• A female fetus
• Oligohydramnios (low amniotic fluid) and polyhydramnios (high amniotic fluid)
• A fetus that is small for gestational age
• Lack of fetal movement during the first half of pregnancy/intrauterine constraint/conditions that limit the baby’s movement in the womb
• History of smoking and alcohol consumption during pregnancy
• Preeclampsia

Normally, a short umbilical cord will be diagnosed during a routine prenatal ultrasound (2). Signs that a patient may be experiencing a short umbilical cord include:

• Non-reassuring fetal heart rates
• Fetal distress

If the diagnosis wasn’t made during a routine ultrasound, signs of non-reassuring fetal heart rates and fetal distress will usually show up in other prenatal tests, such as biophysical profiles or non-stress tests.

Both shorter and longer umbilical cords are associated with increased risk of complications (4). A short umbilical cord can be diagnosed during the first trimester via ultrasound examination. During this exam, the specialist should be taking cord biometrics, including cord length, characteristics of the cord’s blood vessels, and the configuration of the cord on both ends (4).

Because of this element of routine ultrasounds, umbilical cord abnormalities are normally diagnosed as a part of this process. The patient has the right to request an ultrasound if she has a concern at any point during pregnancy, however.

Placental abruption is the biggest complication of a short cord because any movement of the baby can pull on the cord’s insertion point on the placenta. This can cause the placenta to pull away from the uterine lining, leading to severe maternal bleeding and hemorrhage. We have seen many cases in which a mother is experiencing placental abruption – with very clear signs – and the medical team fails to act appropriately, causing a delay in delivering the baby. When signs of placental abruption are present, the medical team must put the mother in a position in which her baby can be delivered immediately by C-section, particularly if it is known that the cord is short ahead of time.

Outside of maternal concerns, a delay in delivery in the case of a short umbilical cord can cause a tear in the cord that affects the baby’s oxygen supply. The baby must be delivered right away to prevent severe oxygen deprivation and brain damage, such as hypoxic-ischemic encephalopathy (HIE) and cerebral palsy.

All labor and delivery units should have the capacity to perform a quick C-section when a baby is showing signs of distress. When a cord is too short, there often is a lot of tension placed on the vessels within it during delivery. This shows up as an abnormal or non-reassuring heart tracing, and an emergency C-section must take place right away. Any signs of fetal distress or non-reassuring heart rate during labor need to be addressed right away.