My MIL and SIL found it works with DH's if the hand is palm down. I guess apparantley they found that way you can do it with your children to see how many and what gender they may have.
Let's see mine goes boy-girl-boy-boy-girl-girl then the hair broke (isn't that weird?). I had a miscarriage a year before DS2 was conceived and felt that it was possibly a girl.
I'm going to try again to see if the hair breaks in the same spot...
Don't know if I'd put too much faith in it but it is fun! 