track your ovulation as best you can. and sex only every other day. His swimmings need some recovery time so they can be stronger when they need to be. we were told from the fertility specialist every other day from CD9-24 So try that and it could help.
With irregular periods it's hard to track ovulation. I've heard folic acid helps.
I would track my ovulation and have sex right a day or two right before ovulation and during. I would also start taking prenatal vitamins.
Good luck!