DEAR DOCTOR K: My periods used to be pretty regular. But for the past few months, I've been spotting all month long. Why is this happening?
DEAR READER: There are many possible explanations. Fortunately, few of them can turn into serious problems. Before talking about the causes of abnormal bleeding from the uterus, it's worth reviewing the menstrual cycle. Normally, the cycle is triggered by signals from sex hormones. Hormones made in the brain travel to the ovaries, leading to the production of other hormones by the ovaries: estrogen and progesterone.