Irregular menstruation, dark red is okay?

Question
Hello doctor, my friend's condition is delayed, usually 1 month, sometimes it comes earlier and sometimes it's only a few days late. The working environment changes shifts every 2 weeks (morning and night), so it may affect the menstrual cycle. When my period comes, the first day I bleed a lot, the second day I bleed a little, the blood is dark red, what's wrong? Thank you doctor!
Anonymous customer question
Reply
Hi! Irregular menstruation, which comes later or earlier than the previous month is called dysmenorrhea. Your friend may have a disorder caused by a working, eating or other medical condition. Bright red blood is the color of a normal and steady menstrual cycle. However, the bright red blood color is only normal if the menstrual blood color is the same every month. If there is a sudden change, such as from dark brown, red-orange to bright red in a short time, it is an abnormal sign. For your peace of mind, I recommend that you arrange a time to go to the gynecology specialist to be examined and consulted by doctors to avoid long-term effects on reproductive function and many other problems.
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