Prenatal detection and obstetric management of true umbilical cord knots using color Doppler and 4D ultrasonography: a report of two cases and literature review

Abstract

Abstract Background True umbilical cord knots are common incidental findings at birth, however, there are limited reports of antenatal diagnosis. True knots are mostly asymptomatic; however, cord related accidents may be encountered. Case presentation We present two cases we diagnosed and followed-up antenatally. We reviewed previous literature and found 16 reports of antenatal diagnosis. In addition to foregoing established risk factors, we noticed an increased risk at first trimester screening in our cases. Conclusions Modern ultrasonography (USG) technology applications are valuable for monitoring knot architecture and compression. We propose monitoring the baby with daily kick counts and biweekly cardiotocography after 28–30 weeks of gestation. Weekly umbilical Doppler pulsatility (PI) measurements of afferent and efferent loops with respect to the gestational age, aids in monitoring the tightness of the knot. The timing and route of delivery should be necessitated by obstetric indications. Vaginal delivery is possible under continuous fetal monitorization during labor.