Hello, Thanks for writing to us. Followings are my comments: 1) Pregnancy depends on proper timing of ovulation & unprotected sexual intercourse. Ovulation occurs approx 14 days before next due date in regular cycle. 2) Late or irregular period may be due to hormonal imbalance, mental stress, ovarian cyst, weight gain, irregular diet habit, thyroid disorder, pelvic infection etc. 3) Above conditions should be ruled out and you need to take cyclic Progesterone pill (D16 to D25) to regularize cycle. You should also continue doctor s prescribed medicine. 4) Ovulation prediction kit should be used in this context to predict ovulation and you should prepare for that day for unprotected sexual intercourse. 5) You would need to do this for at least 6 months to 1 year to make sure that you have given the natural process a chance. 6) Vitamin E, Zinc and folic acid supplements are very much helpful in improving fertility and chance of pregnancy. If with the above procedure, you fail to conceive, then you may need some initial investigation to narrow down the possibilities. These include: 1) Fresh semen analysis for husband 2) Ultrasound pelvis to check reproductive organs grossly. 3) Hystero salpingography (HSG)-for tubal patency test. 4) Hormonal test-thyroid profile, LH/FSH, Oestrogen & progesterone level. 5) For ovulation- Day 21 progesterone level assay or serial ultrasound on day 12-16 for follicle measurement. 6) For cervical factor- Post coital test & anti sperm antibody test. 7) Blood sugar (PPBS) etc. Hope, it will be helpful for your information. Good luck.