To analyze the association between grand multiparity and maternal and neonatal morbidity and mortality. Retrospective cross-sectional study. Point G National Hospital, a tertiary care hospital in Bamako, Mali. All singleton births from 1985 to 2003. Cross-sectional study of 13 340 singleton births at a tertiary care hospital in Mali (1985-2003) compared outcomes between 3617 grand multiparas (para ≥5) and 9723 pauciparas (para 1-4). Odds ratios (OR) were adjusted for maternal age, prenatal care utilization, socioeconomic status, and region of origin. Maternal mortality, perinatal mortality, placental abnormalities (previa and abruption), uterine rupture, postpartum infection, postpartum hemorrhage, eclampsia, cesarean delivery, mean birthweight, low birthweight, high birthweight. Grand multiparas were older, poorer, and less likely to have accessed prenatal care. Grand multiparas had a lower adjusted odds of maternal death (adjusted OR, 0.66; 95%CI, 0.45-0.97), but higher adjusted odds of perinatal death (adjusted OR, 1.33; 95%CI, 1.12-1.59), placental abnormalities (adjusted OR, 1.57; 95%CI, 1.21-2.05), and high birthweight (adjusted OR, 1.42; 95%CI, 1.05-1.92). The healthy person effect may explain grand multiparas' lower odds of maternal death. Reducing grand multiparity and improving grand multiparas' access to prenatal care may improve population-level perinatal outcomes.