The Impact of Opt-In versus Opt-Out Consent Process for the Use of Donor Human Milk on Feeding Practice and Growth Pattern in Preterm Neonates

This study aimed to assess the impact of an opt-out consent process compared with the opt-in consent process for using pasteurized donor human milk (PDHM) on feeding practices and growth in preterm neonates. A retrospective study of 200 neonates ≤28 weeks' gestation compared the effects of opt-in versus opt-out consent processes on time to first enteral feed, feeding types, growth trajectories, and prematurity-related morbidities. Descriptive statistics were used to compare the two groups. The opt-out process did not significantly alter the time to the first enteral feed (range opt-in: 0–12 days vs. opt-out 0–5 days, Mann–Whitney U; p = 0.295). Compared with the opt-in process, the opt-out process was associated with less formula use, less mother's milk use, and more PDHM/mixed mom's milk-PDHM use in the first 4 weeks of life (p < 0.01). Unadjusted analyses showed a greater weight gain in the opt-out group on days of life/DOLs 14 and 28 (2.49 [0.20, 4.78] and 3.94 [0.07, 7.80]%, p < 0.05), and following adjustment, it remained significant for DOL 14 (1.87 [0.02, 3.71]). Prematurity-related morbidities were similar between the two groups. The opt-out consent process may impart short-term growth benefits in preterm infants. However, long-term outcomes require further study.