The relationship between living in a physical abusive relationship and adverse outcome of pregnancy was examined using a structured interview including an obstetrical history. Sixty-six women living in a physically abusive relationship, and 114 women randomly selected and not presently living in such a relationship were interviewed. The women reported 312 completed pregnancies. Five of these were twin pregnancies and one was a stillbirth without information on birth weight. Of the 306 pregnancies included in the analysis, violence had occurred in 40. The mean birth weight of births reported by women exposed to violence during pregnancy was 229 g less than the equivalent figure in non-exposed pregnancies. Adjustment for education, primiparity, and history of addiction reduced the difference in mean birth weight to 175 g.