['The method of "massage therapy" has consistently shown increased weight gain in preterm infants. The weight gain was apparent during massages administered by professionals.', 'To replicate the results of increased weight gain in the course of "massage therapy" in preterm infants, and utilize a new, cost-effective application of this method by comparing maternal to nonmaternal administration of the therapy.', 'Random cluster design.', 'The study comprised 57 healthy, preterm infants assigned to three groups: two treatment groups--one in which the mothers performed the massage, and the other in which a professional female figure unrelated to the infant administered the treatment. Both these groups were compared to a control group.', 'Over the 10-day study period, the two treatment groups gained significantly more weight compared to the control group (291.3 and 311.3 vs. 225.5 g, respectively). Calorie intake/kg did not differ between groups.'] Does massage therapy by mothers and trained professionals enhance weight gain in preterm infants?