Uriclarity Program Reduces Perceived Insufficient Milk Supply in Early Postpartum: Randomized Controlled Trial

Background: Perceived insufficient milk supply (PIMS) is a common early postpartum concern; this study tested whether a brief predischarge program (Uriclarity) reduces PIMS in the early postpartum period. Methods: Parallel-group, superiority, single-blind randomized trial (1:1; computer-generated simple randomization; allocation concealment with sequentially numbered opaque sealed envelopes). Outcome assessors and the data analyst were blinded. Conducted in three public hospitals in Piura, Peru. Participants were postpartum women ≥18 years, 24–48 h after term birth, exclusively breastfeeding. Interventions: Uriclarity—2-hour in-person educational workshop during discharge plus standardized WhatsApp messages/videos through the first two days after the workshop—versus routine pre-discharge breastfeeding counseling. Primary outcome was PIMS (MILQ, 0–8; higher = better perceived sufficiency) on days 1, 3, 7, and 14. Between-group comparisons used the Wilcoxon rank-sum test; the prespecified primary analysis was a cumulative-link proportional-odds mixed model (random intercept), adjusted for maternal age, parity, and education; intention-to-treat. Results: Of 114 screened, 100 were randomized (54 intervention; 46 control) and all were analyzed. At each follow-up, medians favored the intervention (all p < 0.001); typical Hodges–Lehmann difference +2.00 points (95% CI 1.00–2.00 to 1.00–3.00). By day 14, 83.3% (40/48) vs 30.2% (13/43) achieved MILQ ≥ 7 (RD +53.1 pp; NNT = 2). The adjusted mixed model showed markedly higher odds of being in a better MILQ category with Uriclarity (OR 10.64, 95% CI 4.26–26.58; p < 0.001). No intervention-related harms occurred. As a secondary finding, the AUS showed modest ROC discrimination (AUC 0.60–0.69) with high sensitivity at AUS ≤ 2. Conclusions: A brief, low-cost program embedded in the discharge workflow produced large, consistent reductions in PIMS over two postpartum weeks. Larger multicenter trials with longer follow-up and hard breastfeeding outcomes are warranted. Trial registration: ClinicalTrials.gov NCT06857461 (prospective; registered February 26, 2025).