Hi, Welcome to Healthcare magic. i am Dr Ramadevi Wani. i will be answering your concerns. Usually the first period after abortion may be delayed. After that the period pattern reverts back to what it was before pregnancy. There are several reasons for irregular delayed period: 1. Stress both mental and physical 2. sudden change in weight 3. hormonal abnormalities ( thyroid, prolactin etc) Since you say ultrasound is normal it is not due to polycystic ovaries or ovarian cyst in your case. If your period continue to be irregular for another 2 cycles, you need to be investigated for above hormones. If they are normal, your doctor may start contraceptive pills for three months to regularize your periods and this helps. I hope I have answered to your satisfaction.