Why do we get lower-back pain during our time of the month? All roads lead to prostaglandins, a chemical your body makes. It triggers uterine muscle contractions, which helps your uterus expel its lining, but can also cause cramping, which leads to back pain. "If you have uterine cramping, it can radiate to the back, and hip pain can radiate to the pelvis. The body's way more interconnected than we even think," says Heather Bartos, MD, a board-certified OBGYN and founder of Be. Women's Health and Wellness clinic in Texas.
Some women might feel more intense pain than others. "Our uterus is either tilted forward, it's right mid-line, or is tilted backward, and those are all normal variants," Bartos says. "If you have a tilted backward uterus or retroflexed uterus, it can then, of course, exacerbate that because it's tipped toward the back. It can create those symptoms even more."