Abstract Body: Preeclampsia (PE), new onset hypertension (HTN) during pregnancy, is associated with activated CD4+ T cells, impaired cognitive function, and changes in cerebral blood flow (CBF) autoregulation. Previously, PE women have been shown to develop neurovascular and cardiovascular disorders earlier in life than those that had uneventful pregnancy. COVID-19 (CV) during pregnancy is associated with an increase incidence of the PE phenotype and is also associated with chronic neurovascular and cardiovascular consequences. Previously, we showed adoptive transfer of placental CD4+ T cells from PE women into athymic nude pregnant rats causes a PE phenotype, however we don’t know the role of CD4+ T cells to cause long-term neurovascular or cardiovascular consequences in PE in the presence or absence of a history (Hx) of COVID-19 during pregnancy. Therefore, we hypothesize that CD4+ T cells from PE patients with and without a Hx of CV causes hypertension and neurovascular dysfunction compared to CD4+ T cells from normotensive patients. One million placental CD4+ T cells from Normotensive (NT), CV Hx NT, and PE patients with or without a CV Hx were isolated and injected interperitoneally (i.p.) into pregnant nude athymic rats on gestational day (GD) 12. Dams were allowed to deliver and aged 12-weeks after delivery. At 12-weeks postpartum, blood pressure (MAP) was measured; CBF autoregulation was measured by laser Doppler flowmetry. The Barnes maze and the novel object recognition behavioral assays were used to assess cognitive function 12-weeks postpartum. A two-way ANOVA was used for statistical analysis. At 12-weeks postpartum, MAP increased in CV Hx PE (153±6, n=7, p<0.05) and PE (150±5 mmHg, n=5, p<0.05) compared to CV Hx NT (121±6, n=6) and NT (116±6 mmHg, n=6), respectively. Behavioral analysis showed CV Hx PE and PE exhibited impaired memory and learning (P<0.05) compared to either NT group. Our findings indicate that rat recipients of CD4+ T cells from PE patients in the presence or absence of CV Hx have HTN and cognitive dysfunction in the postpartum period compared to recipients of control CD4 + T cells. These data indicate the importance of CD4+ T cells in long-term consequences of PE and COVID infection during pregnancy.