hello Irregular periods can be either hypermenorrhea( coming too frequently) or hypomenorrhea( coming later than expected dates). both have various reasons. iregular periods can be again either with ovulating or without ovulating. since you said you have difficulty conceiving yours may be without ovulating. there can be many reasons for this. you said your reports were normal but you didn t mention which reports ( eg. ultrasound or hsg or hormonal assays) . also you did not mention for how long you have been trying to conceive. as in order to treat infertility doctor needs to ask couple if they have been having sufficient coitus(thrice a week) for period of at least 12 months. and last but not least checking your partner for infertility is also equally important. hope this helps. if you have any further questions please dont hesitate to ask.