Prospective study on the sonographic Evaluation of umbilicalcord coiling Index in late second trimester and its Association with perinatal outcome

INTRODUCTION: The umbilical cord is the major feto maternal unit that provides communication between the placenta and fetus. It is the life line of the fetus as it supplies water, nutrients and oxygen. It is vital to the development, wellbeing and survival of the fetus. It has 3 blood vessels that pass along the length of the umbilical cord in a coiled fashion. The umbilical cord is protected by Wharton’s jelly, amniotic fluid, helical pattern & coiling of vessels. The coiling property of cord vessels was described as early as 1521 by Berengariusand confirmed by Columbus in 1559 and by Frantius in 1564. Of the many characteristics of the human umbilical cord, the most mysterious and intriguing one is the twisted or spiral course of its component blood vessels. In 1600, Fabricius demonstrated that both right (dextral) and left (sinistral) helices of the umbilical cord exists. If umbilical cord twists were to be randomly determined both twists will be of equal incidence. However, many investigators have found that the majority of the cords have a left-sided twist. The umbilical coiling was first quantified by Edmonds in 1954 who divided the total numbers of coils in the umbilical cord by the length of the cord in centimeters and called it “The Index of twist”. He assigned positive and negative scores to clockwise and anticlockwise coiling respectively. Strong et al later simplified by eliminating the directional scores and named it “The Umbilical CoilingIndex”. AIM OF THE STUDY: To find out whether coiling index in the late second trimester is associated with adverse perinatal outcome at IOG, Chennai. MATERIALS & METHODS: Prospective Analytical study. Period of study: 2011 to 2012, Place of study: Institute of Obstetrics & Gynaecology, Egmore, Chennai. Chennai, Ethical Clearance: The Institutional Ethical Committee clearance was obtained. Selection of cases: Antenatal women coming to Institute of Obstetrics and Gynaecology, Chennai for follow up and delivery were included in the study. Inclusion criteria: Antenatal women with Singleton pregnancy, • Delivering at our institution. Exclusion criteria: Multiple pregnancy, • Anomalous babies, • Malpositions, • Single umbilical artery, • Previous cesarean section, • Inability to measure coiling index. The Umbilical cord coiling index was calculated sonographically between 24-28 weeks. SUMMARY: A total of 300 women who met the inclusion criteria were included in the study. • Thecoiling index as detected by the ultrasound between 24-28 weeks. The mean coiling index in the study group was 0.38. • 236 patients belonged to the normocoiled group, 37 patients belonged to hypocoiled group and 37 patients belonged to hypercoiled group. • They were followed up until delivery and details regarding the gestational age of delivery, mode of delivery, colour of liquor, fetal heart patterns during labour, birth weight and APGAR were noted. The data was analysed. • Abnormal coiling index was found to be associated with age.30 yrs of age were associated with abnormal coiling index. • Coiling index was not associated with parity or any other medical disorders in the mother. • Preterm deliveries, low birth weight babies, abruption, intra uterine death and hypertensive disorders of pregnancy were significantly associated with hypocoiling. • Meconium stained liquor was significantly associated with hypercoiling. • GDM in the mother, increased rate of emergency caesarean sections, abnormal fetal heart rate patterns, and increased rate of admission to NICU were associated with both hypocoiling and hypercoiling. • Thus both hypocoiling and hypercoiling are associated with adverse perinatal outcomes. CONCLUSION: Abnormal coiling index is known to be associated with adverse perinatal outcomes. Coiling index should become a part of routine antenatal ultrasound. Hence if the coiling index is measured in the antenatal period , it would act as a predictor of adverse perinatal outcome and alert the obstetricians and the paediatricians. Studies regarding the most appropriate time of measurement of the umbilical cord coiling index that would accurately reflect the perinatal outcome are yet to come. The correlation of the antenatal coiling index with the postnatal coiling and thereby the reliability of the ultrasound are to be studied