Association of umbilical coiling index by colour Doppler ultrasonography at 18-22 weeks of gestation and perinatal outcome

Abstract

Objective: To study the association between antenatal umbilical coiling index (aUCI) and perinatal outcome.

Methods: 600 primigravidas with uncomplicated singleton pregnancies had an ultrasonography between 18 and 22 weeks of gestation for aUCI by colour Doppler. The aUCI was calculated as the reciprocal of the distance between a pair of coils. It was then correlated with the following pregnancy outcomes: birth weight, mode of delivery, meconium staining of liquor, Apgar scores and gestational age. The results were statistically analysed by χ(2)-test.

Results: The mean aUCI was 0.41. Undercoiling was associated with spontaneous preterm delivery (47.87 %), low Apgar score (52.13 %), LBW (52.59 %), FGR (21.28 %) and NICU admission (76.34 %). Overcoiling was associated with preterm deliveries (65.38 %), increased caesarean sections (61.54 %), meconium staining of liquor (67.31 %), low Apgar score (63.46 %) and NICU admission (72.55 %). There was a positive strong correlation between aUCI and birth weight (r = +0.426).

Conclusions: Abnormal coiling is strongly correlated with low birth weight.

Keywords: Antenatal umbilical coiling index; Hypercoiling; Hypocoiling; Low birth weight; Perinatal outcome.

Figures

Fig. 1

Colour Doppler view showing normal coiling of the umbilical cord

Fig. 2

Both normal coiling and hypocoiling of different segments of the same umbilical cord on colour Doppler

Fig. 3

Almost straight umbilical cord on Doppler

Fig. 4

Hypercoiled cord on Doppler