Abstract: OBJECTIVE: To compare breastfeeding (BF) initiation among 317 women with chronic hypertension (CHTN) and 106 women with CHTN superimposed on pregestational diabetes (CHTN-DM) who intended exclusive or partial BF. METHODS: Retrospective cohort study of women who delivered at≥34 weeks of gestation. At discharge, exclusive BF was defined by direct BF or BF complemented with expressed breast milk (EBM) while partial BF was defined by formula supplementation. RESULTS:CHTN and CHTN-DM groups were similar in prior BF experience (42 vs 52%), intention to BF exclusively (89 vs 79%) and intention to partially BF (11 vs 21%). Women in the CHTN group were younger (31 vs 33y), more likely primiparous (44 vs 27%), and delivered vaginally (59 vs 36%) at term (85 vs 75%). Women in the CHTN-DM group had higher repeat cesarean rates (32 vs 18%), preterm birth (25 vs 15%), neonatal hypoglycemia (42 vs 14%) and NICU admission (38 vs 16%). At discharge, exclusive BF rates among CHTN was higher (48 vs 19%), while rates of partial BF (34 vs 44%) and FF (18 vs 37%) were lower than in the CHTN-DM group. BF initiation (exclusive plus partial BF) occurred in 82%of CHTN and in 63% of CHTN-DM. CONCLUSION: Although intention to BF was similar, BF initiation rates were higher for the CHTN compared to the CHTN-DM group. Exclusive BF was low in the CHTN and even lower in the CHTN-DM group signaling the need for targeted interventions if BF initiation rates are to be improved.