Tummy ache back pain may be pregnant, but also may be caused by the imminent onset of menstruation, acute gastroenteritis and other reasons. 1. Pregnancy: During early pregnancy, due to elevated hormone levels, some pregnant women may experience uterine contraction pain without uterine bleeding or abdominal distension, which may manifest as mild stomach pain and back pain, etc. You can confirm whether you’re pregnant by measuring your blood HCG (human chorionic gonadotropin) levels. 2. Imminent onset of menstruation: Due to pelvic floor congestion and increased secretion of prostaglandins before the onset of menstruation, some women may experience discomfort in the lower abdomen and lumbosacral area or uterine contraction pains, which may be accompanied by diarrhea, and pregnancy can be ruled out by ultrasonography and blood HCG test, and menstruation will usually occur soon after. 3. Acute gastroenteritis: nausea, vomiting, diarrhea and other symptoms occur after unclean or improper diet, can also cause stomach pain and back pain and other symptoms, combined with the medical history, clinical manifestations can assist in the diagnosis. When a woman has a stomachache and low back pain that persists without relief, she can go to the hospital to find out the cause.