Human T-cell lymphotropic virus type 1 (HTLV-1) infection poses significant challenges to maternal and neonatal health, particularly in endemic regions. Vertical transmission, which occurs most commonly through prolonged breastfeeding and rarely during pregnancy, or childbirth, perpetuates the virus within families. This observational, retrospective study analyzed HTLV-1-infected and uninfected pregnant women admitted for delivery at a university maternity hospital in Salvador, Brazil (2020–2022). Medical records provided sociodemographic, clinical, and laboratory data. The HTLV-1 infection rate was 4.61 per 1000 deliveries. The sociodemographic characteristics were similar between infected (n = 17) and uninfected (n = 34) women. HTLV-1-positive women had higher rates of unplanned and undesired pregnancies. Adverse pregnancy outcomes were frequent in both groups (94.1% vs. 91.2%), but metabolic disorders and hypertension/eclampsia were more common among the infected women. Preterm birth and postpartum complications were also more frequent (17.6% vs. 5.9%, respectively), although the difference was not statistically significant. Breastfeeding initiation within the first hours of life was lower among exposed newborns (28.6% vs. 70%; p = 0.013). Neonatal characteristics did not differ significantly between the groups. These findings highlight critical gaps in reproductive health awareness and barriers to accessing preventive interventions. Further research on therapeutic strategies is urgently needed to support the World Health Organization’s (WHO) goal of eliminating HTLV-1 vertical transmission by 2030.