Size of Y axis label is affecting the figure size when saving in eps format

 I trying to make sure that the figure I generate from matlab can be directly imported into my word processor without any scaling so that the font size matches. For that I am fixing my paper position to lets say [0.25 0.25 6 4]. Now when I save my figure in eps format, my figure position is changing with the length of Y axis label (I dont mean the fontsize but the actual length). For example, for a longer y axis label, my figure is pushed more to right and I am having more white space on the left of the figure. Can you please let me know how to fix it?

Thanks