How pregnant is the cat? If very pregnant, I'd think the cat would be top/side heavy and wouldn't want to play.
Otherwise, I would think it's okay. I wouldn't necessarily initiate play time, but if something grabs her attention (like a bug or mice), then let her go after it. (Though perhaps not eat it.) I'd also re-cat proof where you live, for example, remove or cushion all sharp objects, including square tables.
Cats are pretty smart about things like that. It's kind of like humans: if you've always exercised, then you can/should continue to exercise during pregnancy.
She is very pregnant, its her 62nd day almost and babies started moving but she is sometimes so active and keeps on chasing after things. Should i stop her from doing so?
I agree with Ritz. Is she is used to being highly mobile, it wont hurt her. Look, in the open a mom must often be mobile. Doing both hunting to get food, and if necessary, fleeing from chasing dogs.
Predators dont give them a break just becuse they are high preg and their time is near. They are attacking just because of it. So it is only good she demonstrates her ability to fight for survival.