BACKGROUND: Screening for hepatitis B virus (HBV) infection in pregnant women to identify newborns who will require prophylaxis against perinatal infection is a well-established, evidence-based standard of current medical practice. In 2004, the U.S. Preventive Services Task Force (USPSTF) recommended universal screening of pregnant women for HBV infection at the first prenatal visit. PURPOSE: To search for large, high-quality studies related to hepatitis B screening in pregnancy that have been published since the 2004 USPSTF recommendation. DATA SOURCES: English-language studies indexed in PubMed and the Cochrane Database of Systematic Reviews and published between 1 January 2001 and 5 March 2008. STUDY SELECTION: For benefits of screening and newborn prophylaxis, we included systematic reviews; meta-analyses; and randomized, controlled trials. For harms of screening, we included systematic reviews; meta-analyses; randomized, controlled trials; cohort studies; case-control studies; and case series of large, multisite databases. Abstracts and full articles were independently reviewed for inclusion by both reviewers. DATA EXTRACTION: Data on the benefits of screening, including benefits of hepatitis B immune globulin and hepatitis B vaccine prophylaxis of newborns of hepatitis B surface antigen-positive mothers, were extracted by 1 reviewer. DATA SYNTHESIS: No new studies met inclusion criteria. A 2006 systematic review of randomized, controlled trials found that newborn prophylaxis reduced perinatal transmission of HBV infection; all relevant trials were published in 1996 or earlier. LIMITATION: The focused search strategy, which was restricted to English-language articles, may have missed some smaller studies or new research published in languages other than English. CONCLUSION: No new evidence was found on the benefits or harms of screening for HBV infection in pregnant women. Previously published randomized trials support the 2004 USPSTF recommendation for screening.