Introduction: It has been estimated that most of the globally available resources for premature infants are invested in developed countries when 95% of them are borned in developing countries where fortification of breast milk is seldom a feasible option.Even supplementing breast milk with formula implies an expense that cannot always be covered. Methods: The question to answer was how to improve, as early as possible, the nutrition of those premature infants surviving the early neonatal period and having no obvious risk factors for inadequate growth other than prematurity, but who are less likely to thrive with exclusive breastfeeding. First we identified a predictor model of the necessity to complement breastfeeding to achieve an adequate growth. Then we applied this model and evaluate growth outcomes when they reached term. We conducted a longitudinal and observational study in an ambulatory clinic, the KMC program in Colombia.110 mothers and their 117 healthy, pre-term were included. Gestational ages at entry at eligibility were between 31 and 36 weeks,107 infants (91.4%) were available for evaluation at term. At entry,infants were classified as low,medium and high probability to be suplemented according to our predictor model.Infant’s weight were monitored daily until they gained 15g/kg/day,then weekly until term.Formula was offered to infants who were not thriving after the days of support according to our protocol Results: Weight,size and head perimeter averages at entry in the KMCP were 2100gr,44cm,32cm and 3058gr,48.9cm,35.3cm when reaching term.Exclusive breastfeeding at term was sucessfull in 75% of patients,19.4% of the patients received a suplement which was suppressed before term and only 0.6% received exclusive artificial milk.These results are better than the results in our previous study when we build our predictor model. Conclusion: Our goal is to reach an optimum nutrition for our premature newborn.We want to take him to his full term date in a condition as similar as possible to the full term newborn that he could not be.Applying our predictive model we were able to improve his nutritional status and at the same time,obtain a greater proportion of exclusive breastfeeding when reaching term.It is a rational,ethical alternative that should be explored in other settings.