OBJECTIVES :To determine the range for the Umbilical Cord Index as a baseline pattern from normal, uncomplicated pregnancies in women of South-eastern Nigeria and to determine the pattern and effect of umbilical cord coiling on antepartum and intrapartum events followed by fetal outcome. METHODOLOGY :Umbilical cords and hospital records of 525 patients were studied in a prospective cross-sectional study design. The umbilical coiling index(UCI) was determined as the number of complete coils divided by the length of the cord in centimeters by an observer blinded for pregnancy outcome. Subjects with umbilical coiling indices below the tenth percentile ,above the 90 th percentile ,and between the tenth and 90 th percentiles were defined as hypocoiled, hypercoiled ,and normocoiled, respectively. Subjects with hypocoiled and hypercoiled cords were compared with those found to have normocoiled cords. Obstetric history and pregnancy outcome of each patient were obtained from hospital records, blinded for the umbilical coiling index. Odds ratios and their 95% confidence intervals were calculated to evaluate associations between undercoiling and overcoiling and adverse pregnancy outcome, using multiple logistic regression.