The commonly used formulas to estimate the depth of umbilical catheter include Dunn's shoulder to umbilical length graph and a birth weight based formula proposed by Shukla and Ferrara in 1986. In Calgary, the most commonly used method for estimation of UVC insertion length is the birth weight based formula (i.e. UVC insertion length = (3 x birth weight + 9)/2 +1). The success rate of achieving the optimum position of catheter tip using this formula ranges from 31-40%. A recent retrospective study reported the use of different surface markers for calculating UVC insertion depth. A distance from base of umbilicus to nipple distance (UN)-1 cm provided the best and most accurate insertion depth of UVC. This formula had accuracy rate of 84% compared with 57% accuracy rate with birth weight based formula.