true knot in the umbilical cord fetal ultrasound

A true knot in the umbilical cord is a serious condition where the umbilical cord forms a knot during pregnancy, potentially cutting off the baby’s oxygen supply. This can lead to various complications, including fetal hypoxia, brain damage, and even stillbirth. While often undiagnosed until delivery, it’s crucial for medical professionals to monitor for signs of a knot, especially in high-risk pregnancies.
Here’s a more detailed look:
True Knot vs. False Knot:
A true knot is an actual knot formed in the cord, while a false knot is a bulge caused by excessive Wharton’s jelly or looping of the cord vessels.
Causes:
Factors like increased cord length, polyhydramnios (excess amniotic fluid), and certain medical procedures (like amniocentesis) can increase the risk of true knots.
Symptoms and Diagnosis:
True knots are often not diagnosed until after delivery, but some women may experience decreased fetal movement in the third trimester. Prenatal ultrasounds can sometimes detect them, but it’s not always easy, especially if the knot is loose.
Complications:
Tight knots can severely restrict blood flow, leading to fetal hypoxia (lack of oxygen). Potential long-term effects include cerebral palsy, brain damage, and developmental delays.
Management:
If a true knot is detected, close monitoring of the fetus during labor is crucial. In some cases, a cesarean section may be necessary to prevent serious complications.
Prevalence:
True knots occur in approximately 0.3% to 2.1% of all pregnancies.