Background: Intrauterine growth restriction (IUGR) is common in premature infants and can significantly impact long-term physical and neurological development. While breastfeeding is the gold standard for nutrition, its role in optimizing postnatal growth for this specific population requires further investigation. Objective: This study compared growth trajectories specifically weight, length, and head circumference between preterm infants with and without IUGR at 1, 3, 6, 12, and 24 months of corrected age (CA) in Rabat. It also evaluated the impact of maternal feeding during the first six months (CA). Methods: This prospective study, conducted at the National Reference Center for Neonatology and Nutrition, followed 45 breastfed preterm infants (25 with IUGR; 20 without). Anthropometric data were collected over two years and compared against WHO growth standards and Fenton curves. Results: Infants with IUGR had significantly lower birth weights and maintained lower weight throughout the follow-up (p < 0.05). At discharge, extrauterine growth restriction (EUGR) was present in 100% of the IUGR group and 80% of the without-IUGR group. By 3 months (CA), EUGR incidence decreased but remained length in the IUGR group (32% vs. 10%). Stunting was consistently more prevalent in IUGR infants: 92% vs. 75% at 1 month (CA), 64% vs. 25% at 3 months (CA), 24% vs. 0% at 6 months (CA), and 12% vs. 0% at 12 months (CA). By 24 months (CA), both groups reached normal weight, length, and head circumference. Notably, the feeding type showed no significant effect on growth parameters at 3 or 6 months (CA) (p > 0.05). Conclusions: IUGR preterm infants exhibit significantly poorer growth than their without-IUGR peers. Although maternal feeding offers essential benefits, it does not fully prevent growth restriction. Continuous monitoring and individualized nutritional management are crucial to optimize long-term outcomes.