I have long-term disability for my job (self-employed). When I asked my insurance agent about trying to get short-term, she told me there really aren't any good options for those who are self-employed (premiums too high, or maternity exclusion). She recommends most of her clients to just save/self-fund their maternity leave.
I met with an Aflac rep just a few weeks ago who was trying to sell me various plans. She told me that you need 4 people for a group plan, but it can be any 4. I decided against it due to rates/payout.
I am considering the hospital plan/sickness that might be worthwhile.
Good luck!