True knot in umbilical cord is formation of knot in the umbilical cord of the fetus inside the uterus. Umbilical cord is a tube like structure that connects the baby in womb with mother. One end of the cord is connected to the baby’s stomach and other end is attached to the placenta. Placenta is a red disc shaped structure attached to inner wall of the uterus. It provides necessary nutrition and blood from mother to the fetus through the umbilical cord.
An umbilical cord has two arteries and one vein. It carries blood from mother to fetus.The umbilical cord also contains a special jelly like substance called Wharton’s jelly. Most of the time Wharton’s jelly prevents formation of knot in the umbilical cord. It also prevents the knot to cause hindrance in blood circulation in majority of cases.
True knots are mostly caused by frequent rotation of the fetus. It usually develops in the first or second trimester. True knot in umbilical cord often impedes activity of fetus, but sometimes it can causes severe reduction of circulation leading to fetal death. This may occur commonly during the time of delivery.Treatment consists of proper management during the time of delivery.
What Causes True Knot In Umbilical Cord?
True knots of umbilical cord occurs predominantly in first and second trimester because on increased movement of the fetus and accumulation of excess amount of amniotic fluid. When the baby moves extensively in the womb it can cause true knots of umbilical cord. However, the condition is not very common and occurs in 1 or 2 percent of cases.
True knots are observed more commonly in male child as compared to females. Multiple pregnancies or twins, long umbilical cord, small for gestational age babies, and excess of amniotic fluid, advanced maternal age, anemia, obesity, gestational diabetes are some of the known risk factors for this condition.
Symptoms Of True Knot In Umbilical Cord
True umbilical knots can be dangerous at time and sometime they may not. If the knot remains lose there is less risk of any harm to the baby. However, in some cases the knot may become extremely tight and in such cases it can cut off supply of blood to the baby.
Circulating blood from the vessels of umbilical cord provides oxygen and other nutrition to the baby. As a result the fetal activity may become less and its heart rate may become abnormal. It mostly occurs after the 37th week of pregnancy. Hence decreased fetal activity of the fetus is vital sign for true knots of umbilicus. A true knot of umbilicus often leads to stillbirth or death of the fetus.
Diagnosis And Treatment For True Knot In Umbilical Cord
Here are following diagnostic modalities of true knots of umbilicus.
- Reduced or abnormal fetal heart rate of the fetus.
- Ultrasound examination is extremely useful for assessing and detecting the knot in umbilical cord.
- Color Doppler sonography.
- Examination of the cord during delivery.
A true knot of umbilicus usually does not require any special treatment since very few cases may have complications. However, when there is a risk factor is known that may cause true knot of umbilicus frequent ultrasonography examination is needed. This helps in determining whether a knot is present.
Once a true knot of umbilicus is diagnosed any time during pregnancy, the pregnant woman must be strictly monitored for well being of the fetus. This is possible with sonogram. In many cases the mother is admitted in the hospital for close monitoring of the fetus. True knots can become tight any time, especially during labor. Hence in many cases cesarean section is performed to reduce the risk fetal distress.