Fracture of bone with an aneurysmal bone cyst during lactation.

A case is presented of a 28-year-old lactating Nigerian mother who developed a pathological fracture of the left humerus following inapparent physical stress. There was radiographical and histological evidence of aneurysmal bone cyst disease involving both humerus. A possible pathogenetic role of bone-calcium dyshomeostasis during pregnancy and, indeed, lactation is entertained. A strong case is made for calcium supplementation in the pregnant and/or lactating mother, especially in the developing countries with an increased probability of marginal nutrition status.