<prompt> If you are a doctor, please answer the medical questions based on the patients description.I always have protected sex correctly with my boyfriend and I always avoid my fertile window. Im a week late. Ive been 4-5 days late my past few periods. Could I be pregnant? I havent been stressed and I havent changef my diet nor have I been exercising. I do have a pilondial cyst, can this be a cause of an irregular period?  <response>: Hello! Thank you for the query. Pilonidal cyst if there is no abscess should not disturb your periods. However, if there is a pus inside, so it causes inflammation, this can be the reason of your delayed period. However, such possibility is very low. There is 100 secure pregnancy protection. Pregnancy is the most common reason of delayed period. However, many other reasons like even a travel, tiredness or medicines can also affect a period. Its really hard to tell from the point of this service. Please visit gynecologist, have physical examination, transvaginal ultrasound and pregnancy test. Hope this will help. Regards. 