The objetive of the study is to evaluate the non-inferiority or the equivalence of the kangaroo care position, in lateral versus traditional one in prone measuring the stability of several parameters in premature infants less than 28 weeks of gestational age during the first 5 days of life.

A non-inferiority clinical trial, controlled, randomized and not blinded has been designed. The non-equivalent, experimental group consist on neonates less than 28 weeks of gestational age who are placed in lateral position while they are on kangaroo care during the first 5 days of life. On the other hand, the control group include neonates less than 28 weeks of gestational age who are in traditional prone position during kangaroo care on the first 5 days of life.

To define the sample size a power of 80% is assumed (β=0,20) and a 95% confidence interval (α=0,05) with a difference of 0,3ºC (SD 0,16) (9,10) in the axillary temperature. A non inferiority margin of 0.2ºC is established and a 10% sample size loss has been assumed. So a sample size of 35 premature in each group has been estimated.

A non probabilistic and consecutive sampling has been defined. The allocation into the experimental (lateral position) or control group (prone position) is going to be randomized.

The main outcome variable is the axillary temperature. However other clinical variables as pain, changes in the vital signs, HIV incidence rate are going to be measured as well.

Inclusion Criteria:

• Premature under 28 weeks of gestational age with mother / father who wants kangaroo care.

Exclusion Criteria:

• Premature infants with mechanical ventilation in high frequency mode,
• Premature infants in the immediate postoperative period of major surgery,
• Premature infants with malformations of the abdominal Wall
• Premature infants who require immobilization
• Premature infants who do not tolerate kangaroo care: hemodynamic, thermal instability or increased stress
• Premature infants with duration of kangaroo care of less than 60 minutes.
• Also excluded are those patients where the kangaroo care provider has an anatomical limitation for carrying out kangaroo care.