Decreasing estrogen can lead to "atrophic" or thin vaginal and uterine tissues, which are more prone to irritation and light bleeding. When to Seek Medical Advice

While spotting is common, it is often classified as (AUB) and should be evaluated by a healthcare professional to rule out other causes. You should consult an OB/GYN if you experience: Is Spotting Normal During Perimenopause and Menopause?

Progesterone typically stabilizes the uterine lining (endometrium). When progesterone levels drop or become irregular, the lining may not shed properly, leading to light, frequent bleeding or "spotting all month".

The primary driver of spotting in perimenopause is the unpredictable rise and fall of hormones, specifically .

During this transition, the ovaries may not release an egg every month. Without ovulation, progesterone isn't produced to balance the estrogen, causing the uterine lining to build up and shed irregularly.