Fibrous dysplasia is a metabolic skeletal disorder in which the medullary spaces of affected
bones are replaced by fibro-osseous tissue. Patients with fibrous dysplasia usually become
symptomatic during childhood; the adolescent patient we describe is unusual because she
was not known to suffer from fibrous dysplasia until she became pregnant and experienced
a dramatic reactivation of the symptoms. The therapeutic implication of this case and
reproductive counselling for young women with fibrous dysplasia are discussed.