Multiple true umbilical knots: a silent risk for intrauterine growth restriction with anomalous hemodynamic pattern

True knots of the umbilical cord can represent a serious complication for the fetus due to the possible alteration in the fetal circulation with consequent intrauterine growth restriction or fetal death. We report a case of 5 true umbilical cord knots associated with severe fetal growth restriction and an abnormal hemodynamic pattern. The Doppler examination showed a hemodynamic pattern characterized by an early alteration in the waveform profile in the fetal venous districts with normal impedance to flow values in both uterine and umbilical arteries. This normal profile of the umbilical arteries remained unchanged until the last stage of hemodynamic decompensation, while the profiles of the uterine arteries remained normal until delivery. This case report suggests that it is important to pay close attention to the evaluation of the fetal cord in situations in which the above described hemodynamic pattern is noted. Although the ultrasound diagnosis of true knots is extremely difficult, the presence of a true knot should always be suspected in the presence of an intrauterine growth restriction fetus when the venous district is altered before the fetal arterial districts after exclusion of other detectable reasons for growth restriction.