Rare cause of stillbirth: a true knot and loop of cord: case report

Abstract

True knot is an extremely rare condition of the umbilical cord. It affects around 0.3-1.3% of all the pregnancies. It can be loose without obstructing the blood flow to the foetus or can be tight enough to exsanguinate the foetus by compromising the blood flow towards the foetus. A 26 years old, gravida 2, para 1, live 1, with previous 1 caesarean section with hypothyroidism came at 40 weeks POG in labour. No complaints. Antenatal history was uneventful. On examination, patient was stable. Patient was explained risk and demits of TOLAC verses ERCD and opted for TOLAC. Delivered a limp baby. There was presence of one tight loop of cord around neck and one tight true knot over the umbilical cord leading to stillbirth. The umbilical cord is the only blood supply to the foetus during the antepartum and intrapartum period. If the true knot is loose, it will not lead to foetal compromise since foetal circulation is maintained. However, at the time of fetal descent through the birth canal, the knot could be tightened. The tightening knot can occlude fetal circulation resulting in an intrauterine demise. The process of delivery should be very careful and if any fetal distress or non-reactive CTG is present, then an emergency caesarean section must be done. Routine continuous cardiotocography can be the best modality to pick distress at the earliest and to achieve a good outcome of the neonate. A good ultrasonologist can detect nuchal cord and true knot during the antenatal scan.