There was news that Mahima was secretly married to a certain businessman in America (thanks to her frequent trips to America). This time though, when she returned to India from America, she was spotted with a huge belly which she tried hard to conceal. This made the rumors stronger.
Now the cat is almost out of the bag. There is a buzz that the man in question is a high profile architect by the name of Bobby Mukherjee and he is not a resident of America but is from Mumbai. Also he has no connection with the Mukherjees of Bollywood.
Mahima had always preferred people from non-films background, so the possibility cannot be ruled out. It is said that this man treats Mahima like Ritu, the ordinary girl (Mahima is her screen name given by Shubash Ghai) rather than a Bollywood celebrity.
There is no confirmation from Mahima's oops Ritu's side as of now. After the painful break up with Leander Paes, Mahima probably is playing it safe.