I don't think that solipsism results from a lack of empathy, but from feeling disconnected from (or emotionally unattached to) physical reality. I'm not qualified to say anything in general about gender, but for me, feeling more connected to physical reality waxes and wanes with my hormones, so I tend to think of a cluster of characteristics (being highly intellectual, detached, etc) as being hormonally regulated in myself. I feel most physically grounded when particular "female" hormones are high, as measured during pregnancy and breast-feeding, etc., and suspect that my immunity to solipsism now is at least partly a result of a steady level of those hormones now. I think that age has even more effect than gender; I feel most grounded now in my thirties, and felt least grounded at the ages 9-12 and in my early twenties.