Weight loss plans that work

My husband and I are have been trying to have our 3rd child, my doctor told me my chance will increase if we lose some weight, we have lost a total of 80lbs just by changing how we eat. But we have very little time to really work out, we both awork ten hour days 5dsys a week. Has any one found a fast work out that really works?? That wont kill you I might add. I have a ripped ACL so im very limited. Any ideas are appreciated