Spontaneous rupture of the unscarred uterus.

Abstract

By presentation of cases of spontaneous (nontraumatic) ruptures of previously intact uteri, we sought to emphasize important aspects of this rare and dangerous event. Two case presentations of oxytocin-associated unscarred uterine rupture and review of pertinent literature are used to study risk factors and accompanying clinical characteristics. Both spontaneous ruptures of previous unscarred uteri were associated with low-dose oxytocin augmentation, bradycardia, and uterine hyperstimulation monitor patterns and occurred at the onset of the second stage of labor. Because of its rarity, further investigation of spontaneous uterine rupture will depend on case presentations where the associated events listed are noted and uterine hyperstimulation, fetal bradycardia, and second-stage onset are proved or disproved as valid clinical associations.