Change is the first sign
One of the first symptoms a woman may notice as she enters perimenopause is changes to her usual menstrual cycle. Bleeding may become lighter or more substantial, the duration of her period may last longer or become shorter and can come in varying intervals.
Increased bleeding
Many women experience heavy bleeding during perimenopause due to lower levels of progesterone, which causes the uterine lining to become thicker before shedding. Other health conditions affecting the uterus, like fibroids, could also be responsible for an increase in flow, so a doctor should evaluate any abnormality you may experience.