The effect on Faraday rotation of stratification in an ionized medium parallel to the direction of propagation is examined. An expression suitable for a general inhomogeneity profile is obtained in a series form. A closed-form solution is also discussed with reference to a lens-like medium described by a parabolic inhomogeneity profile. The departure of rotation from the first-order value is shown to have a strong dependence on the nature of the inhomogeneity distribution. Near the focal points within a focusing medium, the Faraday effect is found to exhibit an anomalous behavior in that rotation changes sign through a large swing in amplitude.