We analyzed a cohort of 2850 live-born triplet sets to compare age, parity, stature, pre-gravid body mass index (BMI), and weekly weight gain in mothers who delivered triplets with a total weight in the 10th, 5th, and 1st deciles corresponding to the heaviest, average-weight, and lightest triplet sets, respectively. Mothers who delivered the heaviest triplets were significantly older, multiparous, taller, heavily built, and gained more weight compared with mothers of average-weight triplets. In contrast, except for higher parity, mothers of average-weight sets were not significantly different compared with mothers who delivered the lightest triplet sets. We concluded that parity was the only significant factor for increased total triplet weight in the first five deciles. However, the presence of other factors in addition to parity is needed for a triplet pregnancy to be included in the 10th decile.