ABSTRACT Umbilical cord knots and nuchal cords are distinct conditions associated with pregnancy and childbirth, known to potentially increase the risk of adverse perinatal outcomes. Umbilical cord knots are rare, occurring in approximately 1-2% of pregnancies, while nuchal cords are estimated to affect around 20-30% of pregnancies.We present a case of a 24-year-old woman, G3P2 with no underlying medical conditions, who presented to a resource-limited setting with hypogastric pain radiating to the lumbar region and vaginal leakage during an unknown gestational age pregnancy. The patient had limited antenatal care, with only a single visit during the fourth month of pregnancy at another health center, where no ultrasound was performed. Physical examination revealed an enlarged abdomen with longitudinal growth and noticeable respiratory movements. Symphysis-fundal height measured 29 cm, and uterine contractions were present. Vaginal examination indicated a mucus-stained vulva and a dilated cervix measuring 5 cm. Absence of fetal heart sounds on Doppler fetoscope examination raised suspicion of intrauterine fetal death; however, no ultrasound was available at the center. Following approximately 10 hours of labor, the patient spontaneously delivered a stillborn male fetus with a true cord knot and three nuchal cord loops. Examination of the placenta revealed a lengthy umbilical cord measuring 128 cm.The coexistence of a true umbilical cord knot (TUCK) and a nuchal cord (NC) can lead to fetal distress. Prenatal ultrasound diagnosis of these conditions is challenging, and there are currently no established guidelines for patient management. A proper delivery protocol with close monitoring is critical.Keywords: True umbilical knot; Nuchal cord; Triple-circular nuchal cord; Fetal demise; Obstetrics; Case Report.INTRODUCTIONUmbilical cord knot (UCK) affects around 0.3–2.1 % of all singleton pregnancies and coexisting with triple-circular nuchal cord (TCNC) is a very scare and highly unexpected complication of pregnancy that can result in fetal demise or neonatal death (1,2). The rate of fetal growth restriction (FGR) is higher in deliveries with UCK compared to normal deliveries, which can be justified by a decrease in fetal blood flow following umbilical cord constriction. Additionally, pregnancies with UCK are associated with a 4–8 times higher rate of fetal mortality in the second and third trimesters (1–3). Multiple umbilical cord entanglements around the fetal neck in singleton fetuses are extremely uncommon and can be potentially hazardous to the fetus, in contrast to single nuchal cord loops, which have a reported prevalence ranging from 15 to 30% (4).CASE DESCRIPTIONA 24-year-old woman, G3P2, with no significant medical history, presented to a resource-limited setting in a low-income country with hypogastric pain radiating to the lumbar region and vaginal discharge of mucus consistency. The gestational age of her pregnancy was unknown. The patient had sought care from a traditional midwife, as she had done with her previous pregnancies, which were successfully managed through physiological home deliveries. Until recently, the current pregnancy had been uneventful; however, the patient became concerned when she noticed a lack of fetal movements, prompting her to seek better medical attention at the center. She had only one prenatal visit during her fourth month of pregnancy at another health center, where she received two unspecified doses of vaccine, but no ultrasound examinations were performed.On examination, the patient appeared anxious and distressed, complaining of hypogastric pain radiating to the lumbar region. Her vital signs were as follows: heart rate 133 bpm, blood pressure 144/104 mmHg, temperature 37 degrees Celsius and oxygen saturation 98%. There was no evidence of jaundice, and auscultation of the lungs revealed clear breath sounds. No pedal edema was observed. Abdominal examination showed an enlarged uterus lengthwise, with palpable respiratory movements and soft consistency. Symphysis-fundamental height measured 29 cm. Uterine contractions were noted, but no fetal heart sounds could be detected using the Doppler fetoscope. Vaginal examination revealed a mucus-stained vulva, a 5 cm dilated cervix with 40% effacement. Fetal presentation was cephalic, with a station of -1. The finger pad of the glove used for the examination was soiled with glairosanguineous secretions. Unfortunately, no ultrasound was available at the center. A provisional diagnosis of probable intrauterine fetal death had been made in a pregnant woman in the active phase of labor.Limited laboratory tests were conducted at the center. The patient’s screening results were negative for Human Immunodeficiency Virus (HIV) and syphilis. Her hemoglobin level was measured at 11 g/dL, with a hematocrit of 33%. She received an intravenous injection of 2 g ampicillin, and a 1 L solution of Ringer’s lactate was administered. Approximately 9 hours later, she spontaneously delivered a stillborn male fetus with three loops of nuchal cord and a true cord knot, as depicted in Figure 1 and Figure 2. Examination of the placenta revealed an umbilical cord measuring 128 cm in length. Based on these findings, a diagnosis of coexisting true umbilical cord knot and triple-circular nuchal cord with fetal demise was established.DISCUSSIONThe umbilical cord (UC) is a vital link between the fetus and placenta, facilitating the exchange of oxygen, nutrients, and waste products. It consists of two umbilical arteries and one umbilical vein, enveloped by Wharton’s jelly, and covered by the amnion (5). The cord forms during embryonic development (weeks 3-7) and typically measures around 50 cm at full term 6. Umbilical arteries transport deoxygenated blood from the fetus to the placenta, while the umbilical vein carries oxygenated blood back to the fetus (7) Hyrtl’s anastomosis provides collateral circulation at the cord insertion in arterial occlusion (8). In the fetal abdomen, the umbilical vein merges with the portal vein, forming the ductus venosus, bypassing the liver and merging with deoxygenated blood in the inferior vena cava (9). Abnormalities in cord length, diameter, insertion, coiling, knots, or vessels can affect fetal growth, blood flow, and oxygenation. Prenatal ultrasound evaluation of the umbilical cord is recommended for detecting potential complications and guiding management (10).TUCK and NC are two conditions that affect the UC and may compromise fetal well-being. The pathophysiology of the UCK and NC is not fully understood, but it is believed that they are caused by excessive fetal movements and variations in the length of the umbilical cord (11). A TUCK occurs when the fetus passes through a loop of the cord, creating a knot that may tighten during labor and delivery, compromising the blood flow and oxygen supply to the fetus (8, 10). A NC occurs when the cord wraps around the fetal neck or other body parts, which may also result in compression and obstruction of the umbilical vessels (10).TUCK is a rare occurrence, reported in approximately 0.04% to 3% of all deliveries (8). Several documented risk factors for TUCK include advanced maternal age, multiple pregnancies, obesity, anemia, a history of spontaneous miscarriages, chronic hypertension, and diabetes mellitus (12). On the other hand, NC is more common, affecting 6% to 37% of all deliveries (10). Risk factors associated with NC include a long umbilical cord, excessive fetal movements, polyhydramnios, monoamniotic twins, and breech presentation (13). In the case of our patient, she had none of the above-mentioned risk factors associated with the occurrence of TUCK and had one of the above-mentioned risk factors for NC since she had an UC length of 128 cm, out of the average length of approximately 50 cm (6).The prenatal diagnosis of TUCK and NC is challenging and often relies on ultrasound examination. However, ultrasound has limitations in detecting these conditions, especially in late pregnancy when the amniotic fluid decreases (13). Color Doppler ultrasound may improve the visualization of the UC and its blood flow. Three-dimensional ultrasound may also provide more detailed images of the cord and its knots (13). However, these methods are not widely accessible, and their results may not provide definitive conclusions. Due to the resource limitations at the healthcare center, the patient was unable to undergo an ultrasound examination upon arrival. Transferring the patient to a community hospital with better resources may have been considered as an alternative. However, in this specific case, there were a couple of factors that influenced the decision-making process. Firstly, there was a suspicion of intrauterine fetal death, and transferring the patient would not have significantly altered the outcome for the fetus. Secondly, the patient was already in the active phase of labor with a cervical dilation of 5 cm, which contraindicated transfer to our center. Moreover, the poor road infrastructure posed a considerable risk, as the journey could have been turbulent, potentially leading to the patient giving birth in the transport vehicle, where no healthcare personnel were present. This situation would have endangered the mother’s life.Authors have reported an association between TUCK (true umbilical cord knot) and adverse outcomes such as meconium-stained amniotic fluid, intrauterine fetal death, low 1-minute Apgar score, premature birth, and admission to the intensive care unit (2, 3, 14, 15). However, some studies suggest that TUCK does not pose a risk during delivery (16) and is not associated with long-term adverse neurological effects (15). NC has also been linked to neonatal intensive care, intrauterine fetal death, premature birth, small for gestational age babies, intrauterine growth retardation, and low Apgar score (17, 18). Tight nuchal cord loops may result in clinical signs such as hypovolemia, hypotension, decreased perfusion, and mild respiratory distress. Additional signs include facial darkness, facial petechiae, subconjunctival hemorrhage, or neck skin abrasion (19). Kong et al. found that nuchal cord with three or more turns was associated with meconium-stained amniotic fluid and suspected fetal distress (18).TUCK is associated with a higher rate of preterm delivery and cesarean section due to a non-reassuring fetal heart monitor and meconium-stained amniotic fluid (3). In contrast, Räisänen et al. reported similar delivery characteristics between women with TUCK and the control group (12). Nuchal cord (NC) as a whole or with a single turn was paradoxically associated with fewer emergency cesarean sections, but for three or more turns, there was a higher incidence of emergency cesarean section. NC, whether as a whole or with multiple turns, was not significantly associated with a higher incidence of instrumental deliveries (20). Narang et al. found an extended second stage in parturient with single or multiple loops of NC, possibly related to the length of the ”linear” segment of the cord rather than the number of loops (21).Currently, there is no specific management for patients diagnosed with TUCK or NC through antenatal ultrasound (22). Routine antenatal ultrasound for nuchal cord is not recommended as it does not influence the mode of delivery or labor management, and the standard labor protocol should be followed (21).ACKNOWLEDGEMENTArens Jean Ricardo Médéus coordinated the project. He was responsible for drafting a portion of the discussion and combining the different parts of the manuscript. He also conducted the revision and formatting of the final manuscript. Ali Mortezaei wrote the introduction, Adams Emmanuel Milhomme wrote the case description, and participated in patient care. Kohlz Erley Saint Jusca contributed to the discussion section, supervised the writing of the case description, and performed proofreading. Kundan Kumar was responsible for writing the abstract.CONFLICT OF INTEREST STATEMENTThe authors declare no conflict of interest.FUNDINGThis research has received no funding.ETHICAL APPROVALWe obtained authorization from the center’s medical director to access the patient’s record and publish the case.CONSENT STATEMENTWritten informed consent was obtained from the patient’s parent for publication of this report, in accordance with the journal’s patient consent policy.REFERENCESLinde LE, Rasmussen S, Kessler J, Ebbing C. Extreme umbilical cord lengths, cord knot and entanglement: Risk factors and risk of adverse outcomes, a population-based study. 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BMJ Publishing Group. https://doi.org/10.1136/bcr-2017-223241FIGURES LEGENDSFigure 1: Stillborn fetus with three loops of nuchal cordFigure 2: One true knot in the umbilical cord wrapped around the neck of stillborn fetus.
