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Sometimes you can experience 1-2 missed periods while being on hormonal contraceptive pills. However, the chances of pregnancy as cause for the missed periods also cannot be ruled out completely. Visit your doctor/gynecologist for further evaluation to look for the underlying cause. Look out for development of any other new symptoms if pregnancy is suspected. If pregnancy is suspected, consider visiting your doctor/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). If pregnancy gets ruled out, further evaluation would be done to look for the underlying cause for your symptoms/absent periods. Treatment as appropriate (based on examination findings and investigations results) would be started to help you control the symptoms and regulate your periods. Be in regular monitoring and follow-up with your treating doctor/gynecologist and report any new/abnormal symptoms immediately. If pregnancy is suspected, or if pregnancy gets confirmed, stop the hormonal birth control use.
Take care.