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If you have taken emergency contraceptive pills (ECP) within 48 hours of the unprotected sexual contact, it should work in preventing pregnancy. Since it contains high doses of hormones, it can disrupt your normal hormonal pattern, and cause bleeding and period abnormalities. Withdrawal bleeding usually occurs after about 5-7 days of taking the ECP. Wait and watch for your next periods/withdrawal bleeding which might be delayed. If periods do not start within 10 days of expected period dates then consider visiting your doctor/gynecologist for further evaluation and assistance. If you suspect to be pregnant, look out for development of any other new symptoms suggestive of early pregnancy.
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