PURPOSE: There is literature suggesting an intergenerational relationship between maternal and infant size for gestational age status and preterm birth, but much less is known about the contribution of paternal birth outcome to infant birth outcome. This study seeks to determine the association between paternal and infant small-for-gestational-age status (weight for gestational age < 10th percentile, SGA) and preterm birth (< 37 weeks gestation, PTB) in a large, diverse population-based sample in the United States. METHODS: Stratified and log-binomial multivariable regression analyses were computed on the vital records of Illinois-born infants (1989-1991) and their Illinois-born parents (born 1956-1976). RESULTS: Among non-Hispanic Whites (n = 83,218), the adjusted (controlling for maternal SGA or PTB, age, parity, education, marital status, prenatal care, and cigarette smoking) relative risk (95% confidence interval) of infant SGA and PTB for former SGA (compared to non-SGA) and preterm (compared to term) fathers equaled 1.65 (1.53, 1.77) and 1.07 (0.92, 1.24), respectively. Among African-Americans (n = 8401), the adjusted relative risk (95% confidence interval) of infant SGA and PTB for former SGA (compared to non-SGA) and preterm (compared to term) fathers equaled 1.32 (1.14, 1.52) and 1.19 (0.98, 1.45), respectively. CONCLUSION: Paternal adverse birth outcome, particularly SGA, is a modest risk factor for corresponding adverse infant outcome, independent of maternal risk status. This phenomenon appears to occur similarly among non-Hispanic White and African-American women.