In light of recently raised doubts about the safety of Cohn fraction II globulins, a prospective study on the risk of transmission of viral hepatitis with a Cohn‐fractionated Rh immune globulin (Rhesonativ, KabiVitrum AB, Stockholm, Sweden) was performed in 47 newly delivered mothers. The women were followed regularly for 6 months after the injection of the Rh immune globulin for biochemical, serological, and clinical signs of viral hepatitis.No clinical signs of acute hepatitis were noted during the study, nor were HBsAg or anti‐HBc found in any patient. A slight and transient rise in alanine aminotransferase (ALT) levels was seen in three women, but these never reached 2.5 times the upper normal limit as is the currently used lower limit for a diagnosis of non‐A, non‐B hepatitis. One woman had positive tests for anti‐HBs at 5 and 5.5 months, respectively, after the injection, but serum samples taken before and after this period were all anti‐HBs negative. Nonspecific reactions in the method used probably explained this finding.This prospective study supports the contention that Rhesonativ, a Cohn‐fractionated Rh immune globulin, does not transmit vi