It's common to experience occasional changes in menstrual flow, from heavier to lighter than usual. Birth control, thyroid disorders, and stress can lead to a lighter period, or even a missed period.
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Why Is My Period So Light?

If your period is light, the flow may appear pink, red, or brownish. You may or may not experience cramps and period pain. A light period or spotting can be just a normal fluctuation, or it may be due ...
You may skip a period or have spotting instead of a period due to stress or certain birth control methods. But it may also occur if you have an underlying health condition. Menstrual periods are the ...