Pregnancy-induced hemorrhagic degeneration of adenomyosis.

Uterine fibroids are known to degenerate during pregnancy, but it is unknown if similar pathologic condition occurs in adenomyosis. A 38-year-old para 1 woman exhibited uterine tenderness and a markedly elevated inflammatory response at 22 weeks of gestation. Based on magnetic resonance imaging (MRI) findings indicative of hemorrhagic components in an adenomyosis lesion, we judged these features resulted from degeneration of adenomyosis after excluding the possibility of underlying infection by amniocentesis. Although these symptoms improved with conservative management, nonreassuring fetal status prompted an emergency cesarean section at 27 weeks of gestation. MRI performed 4 months postpartum revealed the degeneration had completely disappeared. The present case confirms the presence of a pathologic condition-transient degeneration in adenomyosis-which is triggered by pregnancy.