In the United States (US), epidemiologists have long documented paradoxically lower rates of adverse perinatal health outcomes among immigrant birthing people than what might be expected in light of socioeconomic and language barriers to healthcare, especially as compared to their US-born racial and ethnic counterparts. However, researchers have also documented significant variability in this immigrant birth paradox when examining within and across racial and ethnic subgroups. This review paper summarizes fifty years of research regarding differences in low, preterm birth, and infant mortality in the US, according to the nativity status of the birthing person. While there is ample evidence of the importance of nativity in delineating a pregnant persons risk of adverse infant outcomes, this review also highlights the relative paucity of research exploring the intersection of acculturation, ethnic enclaves, and structural segregation. We also provide recommendations for advancing the study of perinatal outcomes among immigrants.