A method of controlling a wind turbine for reducing fatigue loads, the wind turbine comprising a wind turbine tower, a nacelle arranged on top of the wind turbine tower, a rotatable rotor with at least two wind turbine blades arranged relative to the nacelle, and a wind turbine control system, wherein the wind turbine control system comprises a controller configured to control the operation of the wind turbine and a sensor unit configured to measure the rotational speed of the rotor, wherein the method comprises the steps of: - measuring a vibration signal indicative of vibrations in the wind turbine; - measuring a rotational speed of the wind turbine; and - comparing the measured rotational speed to at least one exclusion zone (18, 19) determined by a width about a predetermined rotational speed, whereby the at least one exclusion zone defines a first rotational speed and at least a second rotational speed, and when the measured rotational speed is within the at least one exclusion zone (18, 19) performing a step of: - adjusting the operation of the wind turbine so that the rotational speed is changed to a rotational speed located outside the at least one exclusion zone (18, 19), characterised in that the method further comprises steps of: - varying the width of the at least one exclusion zone (18, 19) as a variable width as a function of the measured vibration signal, and - applying a transfer function to the vibration signal, wherein the transfer function is indicative of at least one transition phase in which the variable width is changed between a first width and a second width. - measuring a vibration signal indicative of vibrations in the wind turbine; - measuring a rotational speed of the wind turbine; and - comparing the measured rotational speed to at least one exclusion zone (18, 19) determined by a width about a predetermined rotational speed, whereby the at least one exclusion zone defines a first rotational speed and at least a second rotational speed, and when the measured rotational speed is within the at least one exclusion zone (18, 19) performing a step of: - adjusting the operation of the wind turbine so that the rotational speed is changed to a rotational speed located outside the at least one exclusion zone (18, 19), characterised in that the method further comprises steps of: - varying the width of the at least one exclusion zone (18, 19) as a variable width as a function of the measured vibration signal, and - applying a transfer function to the vibration signal, wherein the transfer function is indicative of at least one transition phase in which the variable width is changed between a first width and a second width. - adjusting the operation of the wind turbine so that the rotational speed is changed to a rotational speed located outside the at least one exclusion zone (18, 19), characterised in that the method further comprises steps of: - varying the width of the at least one exclusion zone (18, 19) as a variable width as a function of the measured vibration signal, and - applying a transfer function to the vibration signal, wherein the transfer function is indicative of at least one transition phase in which the variable width is changed between a first width and a second width. - varying the width of the at least one exclusion zone (18, 19) as a variable width as a function of the measured vibration signal, and - applying a transfer function to the vibration signal, wherein the transfer function is indicative of at least one transition phase in which the variable width is changed between a first width and a second width.