Is nuchal cord justified as a cause of obstetrician anxiety?

Abstract

Purpose: Birth asphyxia leading to acidosis comprises 20-60 % of perinatal mortality. Nuchal cord (NC) is one of the possible causes of birth asphyxia. Majority of fetuses who are antenatally detected to have nuchal cord are able to achieve successful vaginal birth. The purpose of this study was to analyze the effect of nuchal cord on fetal acid base status and perinatal outcome in vaginal deliveries.

Study design: 150 parturients were equally divided into three groups after vaginal delivery based on no NC, single and multiple loops. Umbilical cord arterial blood was analyzed for biochemical markers i.e. pH, PO2, SPO2, PCO2, HCO3 (-), standard base excess and lactate for acidosis. Labor complications like abnormal FHR, meconium-stained liquor, prolonged second stage, instrumental vaginal delivery, third stage complications were compared. In neonates, birth weight, Apgar score ≤7 at 5 min, NICU admission and other morbidity and mortality during hospital stay were compared among groups using suitable statistical tests. Above parameters were also compared between tight and loose loops.

Result: Nuchal cord groups had significantly higher frequency of labor complications than no NC group, especially tight loops. Neonates with NC had significantly higher frequency of meconium-stained liquor, Apgar score ≤7 at 5 min, deranged biochemical markers, NICU transfer. However, none of the neonate had pH in acidosis range and majority were discharged in healthy condition.

Conclusion: Patients with NC are likely to have uneventful labor and delivery as cord compression is transient and most fetuses are able to compensate for reduce umbilical blood flow. Routine antenatal ultrasound scan is not advisable, as mode of delivery and labor management does not change with detection of NC antenatally. Therefore, vaginal delivery with routine labor protocol can be allowed in cases of nuchal cord.