Karaaslan, OnurCakir, Ali2026-04-022026-04-0220262667-663X10.4328/ACAM.22959https://hdl.handle.net/123456789/30208https://doi.org/10.4328/ACAM.22959Aim: This study aimed to investigate the relationship between the postnatally measured umbilical cord coiling index (UCI) and the antenatally assessed umbilical artery (UA) Doppler systolic/diastolic (S/D) ratio in high-risk pregnancies. Methods: A total of 491 singleton pregnancies over 24 weeks of gestation were evaluated. Participants were divided into two groups. The UA S/D ratio was measured in the antenatal period for all cases. After delivery, UCI values were calculated. Based on UCI values, cases were categorized as hypocoiled, normocoiled, and hypercoiled. Results: In the high-risk pregnancy group, fetal birth weight was lower, and the UA S/D ratio was significantly higher (p < 0.01). The mean UCI values were calculated. No statistically significant correlation was observed between UCI and UA S/D ratio overall. A significant difference was found between the type of delivery and UCI categories; vaginal deliveries were more common in the control group (p < 0.01), while there was no significant difference between groups in terms of cesarean section rates (p = 0.32). No significant difference was observed between groups in neonatal intensive care unit admission rates (p = 0.414). Conclusion: UCI may be associated with the type of delivery and certain perinatal outcomes. As there are limited studies on this subject in the literature, more comprehensive and prospective studies are needed to evaluate the feasibility of using UCI in routine antenatal screening.eninfo:eu-repo/semantics/openAccessUmbilical CordDoppler UltrasonographyHigh-Risk PregnanciesArticle