Transient osteoporosis of the hip in pregnancy.

A patient is presented with transient osteoporosis of the hip occurring in the third trimester of pregnancy. This syndrome is characterized by hip pain, limited motion, and osteoporosis of the femoral head with preservation of the joint space. The syndrome is self-limited with full recovery in three months to one year. Treatment is symptomatic with bedrest, protected weight-bearing, and analgesics as needed. The cause of this syndrome remains unknown.