Aim: The aim of this study was to investigate the possible maternal and fetal factors, which affect the Umbilical Coiling Index (UCI). Methods: This prospective, observational, analytic study was conducted using the data of 380 women with term pregnancy and newborns who presented at a University Hospital. Hemoglobin (Hb), ferritin, iron, and the total iron binding capacity (TIBC) of the maternal blood were measured, and transferrin saturation was estimated based on the ratio between serum iron and TIBC. Blood gases, ferritin, iron, and TIBC of the umbilical cord were also measured, and the transferrin saturation was calculated. The length and thickness of the umbilical cord, numbers of coilings, weight of placenta, neonatal weight were registered. The UCI was calculated dividing the total number of coils by the length of the umbilical cord (in cm). Results: A positive, linear, and statistically significant relationship was found between the UCI scores and the umbilical cord blood transferrin saturation, umbilical cord thickness, and the first- and fifth-min APGAR scores (p = .044, p < .001, p = .008, p = .022, respectively). No statistically significant relationship was found between the maternal Hb values and the UCI scores (p = .472). In addition, there was no statistically significant relationship between the UCI scores and maternal ferritin, maternal transferrin saturation and umbilical cordon ferritin levels (p = .940, p = .681, and p = .975, respectively). Conclusions: A positive correlation was found between the UCI and umbilical cord transferrin saturation and between the newborn APGAR scores. However, this finding is not sufficient to explain the relationship of the umbilical cord dynamics with the newborn wellbeing and coiling.