Infection by Listeria monocytogenes in pregnant women may result in fetal loss or invasive disease in the newborn. We examined listeriosis cases reported through the U.S. Listeria Initiative during 2004-2007. Cases were classified as pregnancy-associated if illness occurred in a pregnant woman or an infant aged <28 days. Of 758 reported Listeria cases, 128 (16.9%) were pregnancy-associated. Maternal infection resulted in four neonatal deaths and 26 (20.3%) fetal losses. Invasive illnesses in newborns (n=85) were meningitis (32.9%) and sepsis (36.5%). Pregnant women with Listeria were more likely to report Hispanic ethnicity (52.8% vs. 25.6%, respectively; OR 3.3 95% CI 2.2-4.8) than mothers giving live birth in the USA during 2005 and were more likely to report consumption of Mexican-style cheese (OR 2.6, 95% CI 1.6-4.2) than were non-pregnant patients with Listeria infection. Pregnant woman comprised a considerable proportion of reported listeriosis cases. Further declines in pregnancy-associated listeriosis will require education about avoiding high-risk foods, and continued regulatory and industry efforts to decrease Listeria in foods.