Although most women with parturient low back pain recover within a few months, it takes years for some patients. We have investigated about women with parturient low back pain complaining for more than 1 year. Medical histories, physical examinations and lumber and pelvic x-rays of 23 women with parturient low back pain were examined. Pain persisted from the back to buttocks for an average of 6.9 years and 22 subjects presented with pressure tenderness of the sacro-iliac joint. Standing, walking, assuming a spinal or lateral position, and taking long strides made the pain more severe. A pubic bone displacement of more than 2 mm was seen on X-ray examination of 11 women. Thirteen women used a soft pelvic band as an effective treatment. Our previous study showed that 12.2% of 990 women had parturient pelvic pain for more than 6 months and consequently parturition may be a risk factor for prolonged low back pain in women.