My balloon molly is pregnant and wont have her babies any suggestions?

Livebearers can and do hold on to their young and refuse to release them if conditions are not to their likeing. The commonest reason is too small accomodation. I would make sure that she is in a large enough container (tank) that is well planted and filtered so that she can understand that her young can/will survive. I would suggest at least a 10gal tank preferably larger.