RESUMO
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.