Yes, you may be pregnant, even if you have had a. Although it is very small, there is a possibility of the surgery reversing, regardless of the time the ligature was made and the woman's age.
What influences the effectiveness of the tubal ligation is when it is made. It is known that when the tubal ligation is performed at the cesarean section, the chances of reversal are much greater than when it is done well after surgery.
Even so, the probability of becoming pregnant it's very small. If your tubal ligation was made at the time of cesarean section, the risk of becoming pregnant is 0,01%. However, if you have had the tubal ligation well after the cesarean, the chance of getting pregnant is 10 times smaller.
So if you have had a tubal ligation and are over 15 days delay in menstruation and other symptoms of pregnancy, you should speak to your gynecologist, family physician or general practitioner to take a pregnancy test. Although not common, you may be pregnant, even lacquered.
