Introduction
The umbilical cord is the conduit connecting the baby to the placenta throughout pregnancy and comprises three vessels, namely two arteries responsible for transporting waste from the baby to the placenta for elimination and one vein for conveying nutrients and oxygen from the placenta to the baby and typically ranging from 55 to 60 cm in length, an umbilical cord is deemed short if its measurement falls below 35 cm. Ordinarily, as the baby moves, the tension on the cord stimulates its elongation, accommodating the growth during pregnancy. A short cord suggests insufficient movement and development of the baby, indicating a potential health concern. Additionally, short cords pose a risk of various delivery complications and birth injuries. Approximately six percent of deliveries involve the presence of short umbilical cords.
What Is the Umbilical Cord?
The umbilical cord is the vital connection between the mother and the developing baby in the womb. Originating from the mother's placenta, the cord attaches to the opening of the baby's stomach. Throughout pregnancy, the umbilical cord acts as a conduit, transporting essential nutrients and oxygen from the mother to the baby and comprising one vein and two arteries encased in a protective layer, which includes Wharton's jelly and is enveloped by the amnion membrane.
The vein carries oxygenated blood rich in nutrients to the baby, while the arteries eliminate deoxygenated blood and waste, returning it to the placenta. Upon the baby's birth, the umbilical cord is clamped and cut. This process is painless for both the baby and the mother since the umbilical cord lacks nerves. The clamped stump naturally falls off within a few weeks, revealing the baby's belly button.
What Are the Different Types of Umbilical Cord Problems?
The umbilical cord is crucial throughout pregnancy in delivering oxygen and nutrients to the developing baby. If the cord faces compression or damage, it can pose life-threatening consequences. A disruption in the flow of oxygenated blood may lead to severe outcomes such as hypoxic-ischemic encephalopathy, cerebral palsy, seizures, intellectual/developmental disabilities, intrauterine growth restriction, and more. Various cord-related complications can impede oxygen supply to the baby, including:
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Nuchal cord (the umbilical cord is wrapped around the baby's neck).
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The umbilical cord prolapses (the cord slips through the cervix before the baby).
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Short cord (the umbilical cord is unusually brief).
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True knot (a knot forms in the umbilical cord).
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Infected or inflamed cord (the cord becomes infected or inflamed).
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Vasa previa (blood vessels from the placenta cross the cervix's opening).
What Is a Short Umbilical Cord and What Are Its Complications?
A short umbilical cord is defined as measuring less than 35 cm at term, although certain researchers and clinicians may extend this threshold to 40 cm or even 45 cm. This situation may lead to several challenges for the baby, as described below:
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Hypoxic-ischemic encephalopathy (HIE).
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Umbilical cord rupture.
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Breech presentation.
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Miscarriage or stillbirth.
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Intrauterine growth restriction (IUGR).
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Placental disruption (difficulty transferring nutrients from the placenta to the baby).
What Are the Risk Factors for a Short Umbilical Cord?
The following are the risk factors for a short umbilical cord, including hereditary factors:
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Women of Average or Lower Weight (Normal or Below Normal Body Surface Area): A woman's body size may influence umbilical cord length, with those of average or lower weight potentially at higher risk.
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First-time Pregnant Women: Women experiencing their first pregnancy may have an increased chance of a short umbilical cord.
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Female Fetuses: Research suggests that umbilical cord length may vary based on the sex of the fetus, with female fetuses possibly associated with shorter cords.
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Conditions Such as Oligohydramnios (Low Amniotic Fluid) and Polyhydramnios (High Amniotic Fluid): Abnormal amniotic fluid levels can impact umbilical cord length, potentially leading to a shorter cord.
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The Fetus Being Small for Gestational Age: If the fetus is smaller than expected for its gestational age, it may be correlated with a shorter umbilical cord.
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Limited Fetal Movement During the First Half of Pregnancy, Intrauterine Constraint, or Conditions Restricting the Baby’s Movement in the Womb: Factors limiting fetal movement early in pregnancy may contribute to developing a short umbilical cord.
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History of Smoking and Alcohol Consumption During Pregnancy: Maternal habits such as smoking and alcohol consumption are linked to an increased risk of a short umbilical cord.
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Preeclampsia: This pregnancy complication, characterized by high blood pressure, can be associated with a short umbilical cord, posing potential risks to fetal well-being.
What Are the Symptoms of a Short Umbilical Cord?
A brief umbilical cord is typically identified during regular prenatal ultrasounds. Indicators of a potential short umbilical cord include:
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Non-reassuring fetal heart rates.
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Fetal distress.
If not detected in routine ultrasounds, signs like non-reassuring fetal heart rates and fetal distress may manifest in other prenatal assessments, such as biophysical profiles or non-stress tests.
What Is the Diagnostic Procedure for a Short Umbilical Cord?
Shorter and longer umbilical cords are linked to an increased risk of complications. A short umbilical cord can be identified in the first trimester through ultrasound examination. During this check, the specialist should measure cord features, including length, characteristics of the blood vessels, and the configuration on both ends. Due to the regular ultrasounds, umbilical cord issues are usually identified. However, if she has concerns, the patient can request an ultrasound at any time during pregnancy.
What Happens in the Case of Placental Abruption and Short Umbilical Cord?
A short umbilical cord poses a significant risk, with the main complication being placental abruption. This occurs when the baby's movement tugs on the cord, potentially causing the placenta to detach, leading to severe maternal bleeding. In such cases, prompt action is crucial. If signs of placental abruption are evident, the medical team should swiftly opt for a C-section to ensure the baby's immediate delivery.
Beyond maternal concerns, delaying delivery due to a short umbilical cord may result in a cord tear, affecting the baby's oxygen supply. Urgent delivery is necessary to prevent serious consequences like hypoxic-ischemic encephalopathy (HIE) and cerebral palsy, conditions associated with oxygen deprivation and potential brain damage.
All labor and delivery units need to be equipped for quick C-sections when a baby displays distress signals. The tension on vessels within a short cord during delivery can manifest as abnormal heart tracings, requiring an emergency C-section—any indications of fetal distress or non-reassuring heart rate during labor demand immediate attention and intervention.
Conclusion
Understanding the role of the umbilical cord in pregnancy is vital, as it delivers essential nutrients and oxygen to the developing baby. A short umbilical cord, measuring less than 35 cm at term, can lead to complications like hypoxic-ischemic encephalopathy and cerebral palsy. Recognizing risk factors, symptoms, and diagnostic procedures is crucial for timely intervention. Placental abruption is a major concern, requiring quick action, often through a C-section, to prevent severe consequences for both the mother and the baby.
