If the umbilical cord of a newborn baby has not fallen off after half a month, it may be caused by individual differences, the umbilical cord stump is too long, or the umbilical cord stump is infected, etc. The umbilical cord of a newborn baby may not fall off after half a month. 1. Individual differences: the umbilical cord of a newborn is not fixed in time, some newborns fall fast, some newborns fall slowly, half a month did not fall is also a normal situation. 2. Umbilical cord stump is too long: if the umbilical cord stump is left for too long, it will be difficult for the stump to fall off within a short period of time. 3. Infection of the umbilical cord stump: If the umbilical cord of a newborn baby is not properly cared for and there is redness, swelling and oozing of fluid, the stump may be infected, and the stump may be prolonged to fall off. Each newborn’s umbilical cord falling time is not certain, the umbilical cord half a month has not fallen, if the umbilical cord does not appear infected, bleeding, etc., just need to do a good job of daily cleaning and care, and wait for the umbilical cord to fall off.