What causes soreness and swelling in the lower left back of women?

Generally, aching and swelling in the lower left back in women may be caused by factors such as the menstrual cycle, pregnancy, lumbar muscle strain, lumbar disc herniation, or pelvic inflammatory disease. It is recommended to seek medical attention promptly, identify the underlying cause, and receive symptomatic treatment under the guidance of a qualified physician. The specific analysis is as follows:

1. Menstrual Cycle

During the menstrual cycle, hormonal fluctuations released by the ovaries may cause contractions of the uterine and pelvic muscles, leading to aching and swelling in the lower left back. Applying a hot water bottle filled to one-third to two-thirds capacity to the affected area for 20–30 minutes can help relieve discomfort through heat therapy.

2. Pregnancy

During pregnancy, the gradually enlarging uterus may exert pressure on surrounding tissues and nerves, potentially causing aching and swelling in the lower left back. Pregnant women should maintain moderate physical activity, such as walking or prenatal yoga, to strengthen muscles and reduce strain on the lower back.

3. Lumbar Muscle Strain

Prolonged poor posture or repetitive腰部 movements can lead to lumbar muscle strain. When muscle fibers are damaged, local microcirculation is impaired and metabolic waste accumulates, possibly resulting in the aforementioned symptoms. This condition may also be accompanied by stiffness and restricted movement in the lower back. Patients are advised to take medications such as ibuprofen tablets, celecoxib capsules, or Dahuoluo capsules under a doctor's supervision, based on individual conditions.

4. Lumbar Disc Herniation

Lifting heavy objects with improper bending or without adequately warming up the back muscles may trigger lumbar disc herniation. Degenerative changes in the intervertebral discs, combined with external forces, can cause the nucleus pulposus to protrude and compress nerve roots or the spinal cord, leading to aching and swelling in the lower left back. This is often accompanied by numbness or weakness in the lower limbs. Patients should follow medical advice and may use medications such as acetaminophen tablets, mecobalamin tablets, or mannitol injection for treatment.

5. Pelvic Inflammatory Disease (PID)

Pelvic inflammatory disease is an infection-induced inflammation of the pelvic organs. The inflammatory response causes congestion and edema in the pelvic organs and surrounding tissues, which may compress nerves and blood vessels, resulting in aching and swelling in the lower left back. This condition is typically accompanied by symptoms such as lower abdominal pain, fever, and pain during intercourse. Under medical guidance, patients may use medications such as ceftriaxone sodium for injection, Kangfuyan capsules, or amoxicillin capsules to alleviate symptoms.

In daily life, it is advisable to avoid prolonged sitting or standing and to engage in regular lower back exercises to promote spinal health.