missed period with tubes tied!

Hi,
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If you had already conceived before getting the tubes tied, then it could be possible that you are pregnant. Other possibilities include ectopic pregnancy if you have conceived after getting the tubes tied. Urine pregnancy tests can show you false negative results due to less concentration of pregnancy hormone (HCG) in urine during early pregnancy and hence cannot be relied upon for accuracy. Blood tests can detect accurately and earlier than the urine tests. Visit your doctor/gynecologist for examination and blood HCG test to confirm/rule out pregnancy. Look out for development of any other new symptoms suggestive of pregnancy.
Take care.