Some sexually transmitted infections can cause an excess amount of clear fluid, so definitely get that checked out, I think clamydia can cause that anyways.

Also, do you find yourself more aroused since starting the Zoloft? I certainly do, so if you're more aroused, then that might be the issue and it doesn't have to be sexual arousal to cause that response, anxiety can also cause women to "get wet" and men to get erections.