This study examines the relationship between maternal weight characteristics and recurrence of macrosomia in 111 non-diabetic women who delivered a second baby following primiparous delivery of a macrosomic infant (> 4500 g). Recurrence of fetal macrosomia was associated with greater maternal body mass index (P = 0.032), greater initial pregnancy weight (P < 0.05) and total weight gain during second pregnancy (P < 0.01). Women delivering a first macrosomic infant should avoid excessive weight gain before and during a subsequent pregnancy.