Immigrant Latinas, particularly of Mexican descent, initially achieve healthy perinatal outcomes. Although this advantage wears off across generations in the United States (US), the early life psychosocial mechanisms that may initiate a cascade of biological vulnerabilities remain elusive. The current investigation aims to understand the extent to which childhood experiences of racism may contribute to elevated levels of C-Reactive Protein (CRP), an early indicator of cardiometabolic risk, during the first postpartum year. Latinas from the Community and Child Health Network (n = 457) retrospectively reported experiences of childhood racism and childhood country of residence via structured questionaries. Interviewers collected CRP bloodspots and height and weight measurements for body mass index at six months and one-year postpartum. Latinas who grew up in the US experienced a steeper increase of CRP levels across the first postpartum year (β = .131, p = .009) and had higher CRP levels one-year postpartum than Latinas who grew up in Latin America. Based on Bayesian path analyses, Latinas who grew up in the US reported higher levels of childhood racism than Latinas who immigrated after childhood (β = .27; 95% Crl = [.16, .37]). In turn, childhood racism mediated the relationship between country of childhood residence and elevated CRP at six months and one-year postpartum, even after adjusting for sociodemographic and behavioral covariates. After adjusting for body mass index, mediational relationships became non-significant. This study is an important first step towards understanding how childhood racism may contribute to post-migratory health patterns among Latinas, particularly cardiometabolic risk one year after childbirth.