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Antibiotic use along with your hormonal birth control pills can affect the efficacy of the birth control pills and unprotected intercourse during this time can lead to pregnancy. If you are not regular with the birth control pill use and have not used additional protection during switchover of the pills, you might not have the effective protection and be at risk for pregnancy. Increased vaginal discharge, vaginal discomfort could suggest chances of pregnancy. Wait and watch for your next periods. If pregnancy is suspected, look out for development of any other new symptoms suggestive of pregnancy and consider visiting your gynecologist at the earliest for thorough examination (to confirm pregnancy related changes/signs in body) and blood/serum HCG level test (to confirm/rule out pregnancy accurately). Consider being in regular follow-up and monitoring of your treating gynecologist and report any abnormal/new symptoms immediately. Take adequate rest. Drink plenty of water. Maintain healthy diet and lifestyle.
Take care.