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Chances of pregnancy can be possible due to possibility of spontaneous tubal recanalization. If you suspect being pregnant, it is important to get pregnancy confirmed/ruled out early. Due to previous tubal ligation, risks for ectopic pregnancy can increase. Do not delay your visit to your doctor/gynecologist for thorough examination (to confirm pregnancy related changes/signs in body) and blood/serum HCG level test (to confirm/rule out pregnancy accurately). If pregnancy gets confirmed, consider getting an early ultrasound scan done to help to know if pregnancy is intrauterine or ectopic along with confirmation of gestational age and viability. Be in regular monitoring and follow-up with your treating doctor/gynecologist and report any new/abnormal symptoms immediately. Take adequate rest. Drink plenty of water. Maintain healthy diet.
Take care.