For women who are not sexually active, if you experience pain in the belly and swelling in the chest before each menstrual period, it is considered a precursor to menstruation. When menstruation is approaching, the uterus and pelvis will be significantly engorged with blood, which may lead to pain in the abdomen, mainly in the form of pain in the abdomen or pain in the lower part of the abdomen, and the estrogen and progesterone in the body will reach a high level before menstruation, which will also reflexively stimulate the phenomenon of chest pain. If the pain does not disappear, consider the pain caused by breast hyperplasia. For women who have had sex, the pain in the belly and the pain in the chest may be caused by pelvic inflammatory disease combined with breast hyperplasia, or it may be caused by pregnancy.