Osteonecrosis of the femoral head associated with pregnancy. Report of two cases.

Osteonecrosis of the femoral head developed in two patients, that had taken oral contraceptives for four and eight years respectively, during pregnancy. There were non demonstrable predisposing factors. The symptoms were first noted during the last trimester, and after the delivery improved significantly. Results of examinations, radiography and scanning were consistent with diagnosis of avascular osteonecrosis of the femoral head. The possibility that the long term use of oral contraceptives, might have played a role in the development of femoral head necrosis is stressed by the authors.