Women are catching up with men when it comes to what they have saved up in their retirement plans and the rate at which they're setting money aside.

According to fourth quarter 2012 data for defined contribution plans administered by MassMutual, the average deferral rate for women participants was 5.38 percent, an increase of 1.6 percent for the quarter. Men deferred an average of 5.81 percent, which was an increase of 1.2 percent from the third quarter of 2012.

According to MassMutual, the gap between what men and women save is gradually and consistently closing. Since the third quarter of 2010, when the average account balance among women participants trailed that of men by 40.49 percent, the gap has been gradually closing. During the fourth quarter last year, the average account balance among women was 38.25 percent behind their male counterparts, an improvement of 2.49 percentage points, or 5.6 percent.