My platies have been pregnant for a long time...

I have two platies that look very pregnant (huge and squared off with bellies that look full of babies) but they have been like that for months. I find fry in my tank, but my girls don't look any smaller... Is my male just keeping them pregnant? Even my guppy has been pregnant for a long time. What's going on?

Your sure they are not suffering from bloat, or over feeding?

I don't feed them enough to cause bloat :/ and I see babies in there