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True knot at the time of delivery: electronic fetal monitoring characteristics and neonatal outcomes

ABSTRACT

Objective

Determine the association between electronic fetal monitoring and neonatal outcomes in the setting of a true knot at delivery.

Study design

This was a planned secondary analysis of a prospective cohort of 8580 women. Patients with and without a true knot were compared and the primary outcome was repetitive late decelerations occurring with at least 50% of contractions. Confounders were adjusted for using logistic regression.

Results

A total of 8580 patients met inclusion criteria and 49 (0.57%) had a TK. There was no significant difference in the rate of repetitive late decelerations in patients with TK (aOR 1.04; 95% confidence interval [CI] 0.25–4.40),other electronic fetal monitoring parameters, or neonatal outcomes.

Conclusion

Neonates with true knots who are delivered at term have similar electronic fetal monitoring characteristics compared to those without true knots and no detectable difference in neonatal morbidity; thus, calling into question the clinical significance of a true knot at term.

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Acknowledgements

Funding

This study is supported by the National Institute of Child Health and Human Development (NICHD) grant number R01H@061619-04 (PI: AGC). EBC was supported by a NIH T32 training grant (5T32HD055172-05) and the Robert Wood Johnson Foundation #74250.

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Correspondence to Ebony B. Carter.

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The authors declare that they have no conflict of interest.

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Carter, E.B., Chu, C.S., Thompson, Z. et al. True knot at the time of delivery: electronic fetal monitoring characteristics and neonatal outcomes. J Perinatol 38, 1620–1624 (2018). https://doi.org/10.1038/s41372-018-0250-4

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