Umbilical and Middle Cerebral Artery Pulsatility Indices as Predictors of a Nuchal Cord: A Retrospective Cohort Study

This retrospective cohort study aimed to evaluate the impact of a nuchal cord at birth on the pulsatility indices of the umbilical artery, the middle cerebral artery, and the cerebroplacental ratio, assessed by Doppler ultrasound within 7 days before delivery. Secondary objectives included assessing the associations between the presence of a nuchal cord and a tight nuchal cord with adverse neonatal outcomes, as well as the correlations between the number of cord loops and Doppler indices and umbilical cord blood gas values.

Data from 203 singleton pregnancies with Doppler ultrasound performed within 7 days before delivery were analyzed. Participants were grouped according to the presence or absence of nuchal cord at birth. Doppler parameters (umbilical artery pulsatility index, middle cerebral artery pulsatility index, and cerebroplacental ratio) and clinical variables, including arterial and venous umbilical cord blood pH, Apgar scores, birth weight, and adverse perinatal events, were evaluated.

The presence of a nuchal cord or a tight nuchal cord at birth did not affect the Doppler parameters in obstetric ultrasound examinations conducted up to 7 days prior to delivery. The presence of a nuchal cord was not significantly associated with adverse perinatal outcomes. A weak but statistically significant positive correlation was observed between the number of cord loops and the middle cerebral artery pulsatility index, with no significant correlation with the umbilical artery pulsatility index, cerebroplacental ratio, or umbilical cord blood pH values.

These findings suggest that the presence of a nuchal cord does not impact the pulsatility index of the umbilical artery, middle cerebral artery, and cerebroplacental ratio, assessed by Doppler ultrasound within 7 days before delivery. Further research is needed to clarify the clinical implications.