Pregnancy and lactation-associated osteoporosis (PLO) is a rare condition diagnosed with vertebral fractures detected in late preg-nancy and early postpartum periods. The incidence of PLO is reported to be 0.4 in 100 000 women. Maternal bone resorption and absorption of calcium from the intestines are increased in order to ensure adequate calcium transfer to the fetus, 80% of which is in the last trimester. Bone mineral density decreases during lactation and is associated with high bone turnover. Although various factors have been suggested to be responsible, the cause and etiopathogenesis of osteoporosis associated with pregnancy and lactation have not been fully elucidated. Herein, we reported a 28 year-old primigravid woman without risk factors for secondary osteoporosis diagnosed with vertebral fractures at postpar-tum third month.