Pelvic inflammatory disease (PID) is a bacterial infection that's usually spread by sex. It affects the parts that help you conceive and grow a baby. This includes your fallopian tubes, womb, ovaries, vagina, and cervix.
You'll have pain on both sides of your lower belly and lower back. It can happen any time of the month.
PID causes abnormal vaginal discharge and, sometimes, spotting. You might have pain or burning during sex or when you pee. Your periods might be heavier or longer. You might run a fever or have nausea and vomiting. You'll need to get the disease treated by a doctor.