Short- and long-term impact of gonadotropin-releasing hormone analogue treatment on bone loss and fracture

Gonadotropin-releasing hormone analogues (GnRH-a) are commonly utilized in moderate to severe endometriosis to induce atrophy of endometriotic lesions. Unfortunately, cessation of therapy can lead to recurrence of symptoms. Therefore, long term therapy is sometimes necessary. GnRH analogues cause an immediate decrease in bone mineral density which usually recovers after cessation of its use. However, this recovery in bone mineral density may not always occur after long term use. In order to prevent the deleterious effects on bone, add-back therapy is used frequently. This review will explore the impact of GnRH analogues on both bone loss and fracture risk as well as describe different add-back regimens.