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You can experience missed periods or lighter periods and also alterations in your period pattern with prolonged use of hormonal birth control pill use. Observe your menstrual cycles for 2-3 cycles, and if the changes are persistent, visit your doctor/gynecologist at the earliest for through evaluation to look for the underlying cause for the changed period pattern and flow. Treatment as indicated (based on examination findings and investigations results) would be started to help you to control the symptoms and regulate your periods. Consider being in regular monitoring and follow-up with your treating doctor/gynecologist and report any new/abnormal symptoms immediately. Drink plenty of water. Take adequate rest. Maintain healthy diet and lifestyle.
Take care.