<s>[INST] I was taking prometrium to trigger a period so that I could ovulate because my husband and I have been trying to conceive. I tested positive for ovulation three days in a row and we had intercourse a day before the tests were postive and on all the days it was positive and after. Three weeks later I have no period and a negative pregnancy test. Is there still a possibility that I am pregnant? [/INST] Hi, I think there can be a chance of pregnancy.  Sometimes delayed implantation occurs. So, wait for one more week and then repeat a urine pregnancy test.  if negative, then you can take some medicines for inducing periods.  If positive consult a doctor.  Hope I have answered your question. Regards Dr khushboo </s>