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Occasional passing of endometrial tissues along with menstrual bleeding is considered to be normal. Observe your periods for 2-3 cycles, and visit your doctor/gynecologist if you have abnormal bleeding/periods. If foul smell or itching etc are associated, it could indicate possibility of infection. If symptoms are getting worse, or if you develop any new/abnormal symptoms, report them to your treating doctor/gynecologist at the earliest. 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.