Big girls

I was told by my doc that because I gained extra weight i cause of stress I have to lose weight to even think about getting pregnant but me an my husband been trying for two an a half years we got a false positive pregnancy test an that broke my heart but I have 3 kids with my child hood love an he has 1 of his own an were just want to join our family's by having our own so today I'm at my peak of ovulation an I hope we can conceive any tips