Preterm birth remains the leading cause of neonatal mortality worldwide, representing a persistent challenge in maternal and fetal care. Scientific evidence suggests that omega-3 supplementation can significantly reduce its incidence, especially in women with low levels of these fatty acids. This letter emphasizes the need to integrate their use into clinical practice and public health policies to improve perinatal outcomes and maternal health.

Introduction. Pre-pregnancy weight and excessive gestational weight gain (EGWG) are risk factors for complications in both the mother and her newborn. Objective. To assess the association between pre-pregnancy weight and EGWG with maternal and neonatal complications in a rural area of Mexico. Methods. A prospective cohort study was conducted including 564 pregnant women with singleton pregnancies. Participants were examined during an initial visit at 8–10 weeks and again between 37 and 39 weeks of gestation to evaluate perinatal outcomes. Pre-pregnancy weight and maternal weight gain were categorized according to the guidelines of the Institute of Medicine (USA). Maternal and neonatal complications assessed included: preeclampsia, gestational diabetes, cesarean delivery, labor complications, preterm birth, small for gestational age (SGA), and large for gestational age (LGA). Multiple r...