Well, as I am wont to say, I know a few women myself, and many of them are Catholic and have positions on these issues identical to Santorum's. It may simply be that the MSM pundits don't have a wide enough scope of friendships with people who think differently than they do. Anyway, the exit polls in Mississippi suggest that women don't vote in a monolith, and that Santorum actually does pretty well with a particular segment of women... married women.
Specifically, Santorum carried married women over Gingrich by 41-25 in Mississippi, while losing unmarried women to Gingrich by 32-31. He won women overall in the state by 35-29 over Gingrich, and carried the state despite losing men to Gingrich by 34-31. The results from Alabama were similar: Santorum carried married women over Gingrich by 38-20.
What conclusions do I draw? Married women (who presumably are also more mature) admire Santorum's obvious faithfulness (in both meanings of the term); they like the fact that he seems to enjoy having a lot of children; they like his traditional morality. They don't like Gingrich's serial marriages and philanderings.
The point of this is that pundits are fools who don't really understand women very well. Grown-up women (for instance, women with daughters) are likely to find Santorum's fidelity and traditional morality appealing.
And, something that the chattering classes probably can't see, because they hate Santorum's politics so much.... he's also a big, tall (6'4"), handsome, strapping guy.
In other words, he probably plays a lot better to the suburban mommies than the pundits think.