<s>[INST] I have my tubes tied 10 years ago. Two months ago I had light bleeding lasting only a few hours and then stopping. Last month was the same. I was exhibiting all the signs of pregnancy but 4 pregnancy tests and a blood test came up negative. This month I have had three days light bleeding and I was sitting at my desk working when all of a sudden a persistant flutter started in the upper left side of my abdomen . When my doctor reassured me i was not pregnant I was relieved and hadn t given it another thought. Now i m worried again. [/INST] HI, thanks for using Chat Doctor Tubal ligation procedures for birth control are usually very effective. During pregnancy the hormone Chat Doctor is released, this can be detected normally from day 12 to 14 past conception and your pregnancy test would have been able to pick it up if it was present. The flutter sensation that you are experiencing may be related to either the intestines or the nerve supply to the muscles or skin of the abdomen. I hope this helps </s>