Safeguarding the Blood Supply: A Comprehensive Analysis of the Frequency and Causes of Donor Deferral in Blood Bank Practice

Abstract

Background: A safe and adequate blood supply depends on rigorous pre-donation screening, yet donor deferral the temporary or permanent exclusion of a prospective donor remains a persistent source of donor and unit loss, particularly in donor systems that rely heavily on replacement donation. Objective: To characterize the demographic and physiological profile of deferred blood donors and determine the relative frequency, pattern, and correlates of the causes of deferral at two private-sector blood banks in Lahore, Pakistan. Methodology: A retrospective, cross-sectional analysis was conducted on 173 consecutively recorded deferred-donor entries from the deferral registers of FMH Blood Bank and Chughtai Lab Bank, Lahore, covering Aug-2025 till jan-2026. Variables included demographic data, donor type, weight, haemoglobin, blood pressure, donation history, primary deferral reason, and deferral type (temporary/permanent). Reasons were grouped into nine a priori categories. Associations between categorical variables were tested with the chi-square test (α = 0.05). Results & Findings: Donors had a mean age of 37.9 ± 11.4 years; 148 (85.5%) were male and 101 (58.4%) were repeat donors. Temporary deferrals accounted for 150 (86.7%) of cases and permanent deferrals for 23 (13.3%). Low haemoglobin was the single most frequent cause (48, 27.7%), followed by recent illness/fever (20, 11.6%) and recent medication/antibiotic use (19, 11.0%). Grouped by category, haematological causes were the leading category (27.7%), while infection-related and medication/vaccination-related causes each accounted for 17.3% and, combined, exceeded the haematological share. Permanent deferral was driven by physical eligibility criteria (13/23) and infectious-risk history/chronic medical conditions (10/23). The distribution of deferral-reason categories differed significantly by sex (χ² = 17.88, df = 8, p = 0.022) but not by donor type (χ² = 3.18, df = 8, p = 0.923), and deferral type did not differ significantly by blood bank (χ² = 2.15, p = 0.142). Conclusion: Reversible, largely preventable causes haematological, infective, and medication/vaccination-related dominate the deferral profile at these centres, while permanent exclusion is driven mainly by fixed eligibility criteria and self-reported infectious-risk history rather than confirmed seroreactivity. Targeted donor health counselling, iron-replete recruitment strategies, and harmonised screening protocols across blood banks could reduce avoidable deferral and safeguard a more sustainable blood supply.