Hello thanks for your query There are many causes of irregular periods. You should be investigated thoroughly to rule out all of them Exercise, stress, anxiety, fluctuations in weight and age around 40 are chief causes. Polycystic ovaries can cause irregular cycles for which various hormonal assays are necessary for diagnosis. Thyroid disorder, adrenal disorder can cause this. Also, some disease within the uterus or ovaries can also lead to irregular cycles. The medications prescribed to you act empirically, and are not known to cause any side effects. However, you should consult a proper Infertility specialist, to get all investigations done, also your partners semen testing and tests to know if both your tubes are open. As your cycles are irregular, it is extremely difficult to pinpoint the days of ovulation, around which, intercourse leads to maximum chances of pregnancy. Also with irregular periods, it is very likely that you might not be ovulating at all. Please consult an infertility specialist, who would perform follicular monitoring by ultrasound for you, and hence advise best days for trying to conceive, as well as treatment for anovulation. Take care.