Has anyone ever had problems getting pregnant cause of their irregular cycle only to get on BC and get prego?

My Fiance and I have been trying to get pregnant for about a year now. (I have a son from another relationship who's 2) I started to get irregular bleeding so my Dr put me on loestrin 24. Its my second month of BC.....I have breakthrough bleeding (called Dr said it was normal). I have 3 more packs he wants me to take. Has anyone benefit from BC to get pregnant? if so, how long did it take you? I'm really hoping it works and need a little encouragement. I would love to hear your true stories on this. Thanks so much!