BACKGROUND: Systemic hypertension (SH) has been reported in 0.2–3% of Neonatal Intensive Care Unit (NICU) patients. The epidemiology of the disease in preterm infants needs further exploration. OBJECTIVES: To assess the incidence, temporal trend, risk factors, clinical characteristics, management and associated outcomes of preterm infants with SH. DESIGN/METHODS: A retrospective population-based study including all infants born between January 2002 and December 2016 at < 31 weeks gestation in Nova Scotia. Patients diagnosed with SH (systolic blood pressure > 100mmHg requiring treatment, before discharge from NICU, or on 3 consecutive occasions during outpatient follow-up), were identified from the Provincial Perinatal Follow-up Database and patients’ charts. All SH patients were compared with matched controls (for gestational age, sex and birth weight). Perinatal data, details of SH and neonatal course were reviewed. Infants who died < 7 days of age were excluded. RESULTS: Out of 935 infants who met inclusion criteria, 109 (13.1%) had SH. Mean gestational age was 27.2 weeks (±1.9) and mean birth weight was 1039.3 g (±281.9) Table 1. Median post-menstrual age at diagnosis was 40 weeks Table 2. There was no significant difference in the temporal trend between the three study epochs (Figure 1). On logistic regression analysis, presence of major congenital anomaly was the only risk factor for SH (aOR 14.7, 95% CI:1.54, 141.2). Antenatal magnesium sulfate was protective (aOR 0.39, 95% CI: 0.20,0.75). 64 SH infants (59%) had nephrocalcinosis at time of diagnosis and the majority (79, 72.5%) were treated with ACE inhibitors. There was no significant difference in mortality (p=1.0) but the median length of stay was higher in the SH patients (p