Objectives: To provide an updated review and examine any trends among congenital malaria cases that might help guide diagnosis, treatment, and public health recommendations. Design: Retrospective case series. Setting: United States. Participants: We reviewed all cases of congenital malaria reported to the US National Malaria Surveillance System between January 1, 1966, and December 31, 2004, including 1 unpublished case from 2005, encompassing all years for which data were collected and available. Main Exposures: Maternal characteristics, including travel history, and malaria treatment. Main Outcome Measure: Characteristics of congenitally acquired cases of malaria. Results: For the 81 cases of congenital malaria reported in the United States in the past 40 years, the predominant infecting species was Plasmodium vivax ( 81%). Most mothers ( 96%) were foreign born, and 55 of 65 women ( 85%), for whom time of most recent exposure was known, were exposed 1 year or less before delivery. A common error in the treatment of infants with congenital malaria was the unnecessary administration of primaquine phosphate for P vivax infection. Conclusions: Health care professionals should have heightened vigilance for malaria in pregnant women who have emigrated from or traveled to malaria- endemic areas within the past year, as well as in their offspring. Such women with episodes of fever during pregnancy should have a blood film to test for malaria performed promptly and should be treated appropriately. Treatment of a mother does not negate the need for heightened vigilance in her newborn. Health care professionals should be aware that congenital P vivax malaria does not need to be treated with primaquine.