In a study of 475 women born around the 1944–1945 Dutch famine, women exposed to prenatal famine more often reported a history of breast cancer than nonexposed women (hazard ratio, 2.6; 95% confidence interval, 0.9–7.7). They also had alterations in reproductive risk factors. Prenatal famine may increase breast cancer incidence. Am. J. Hum. Biol. 18:853–856, 2006. © 2006 Wiley-Liss, Inc.