Umbilical cord knot
Entanglement of the umbilical cord that can compromise fetal circulation if tightened.
Full Definition
An umbilical cord knot is a literal knot in the umbilical cord that forms when the fetus passes through a loop of cord during fetal movement. True knots occur in approximately 1% of pregnancies and are more common with polyhydramnios, monoamniotic twins, or excessive fetal activity. Most knots remain loose and cause no problems, but tight knots can compromise blood flow and lead to fetal hypoxia, growth restriction, or stillbirth. Prenatal diagnosis is challenging but may be suspected with abnormal fetal heart rate patterns or sudden changes in fetal movement.
Usage
Usage note: Distinguish between true knots and false knots (vascular prominences) in documentation.
In Context
- "A true umbilical cord knot was identified at delivery, explaining the variable decelerations." — Delivery note
- "The tight cord knot likely contributed to the intrauterine growth restriction noted on ultrasound." — Pathology report