Premature birth can lead the mother to lose control of herself, and be a contributor to the psychological stress experienced due to the sudden breakdown of the interaction with her infant because of hospitalization in a neonatal care unit. This is a mixed method study, the aim is establish the effectiveness of expressive writing in the experience of mothers of hospitalized preterm infants. The intervention Expressive writing therapy could contribute to reduce the level of stress and anxiety, improving coping and the mother's interaction with her infant.

Background: The literature has shown the application of expressive writing therapy after traumatic events, and the measurement of its impact on people´s health through the application of quantitative instruments. However, no studies have been carried out in which this therapeutic activity has been measured with quantitative methods and at the same moment, to measure the experience using qualitative analysis that allows to understand in depth the human experience. Expressive writing therapy could contribute to reducing the level of stress and anxiety, improving coping and the interaction of the mother with her premature newborn (PNTBs). In this sense, it is necessary to have a scientific research in this area, from a qualitative-quantitative approach allows demonstrating the reach of positive effects in the emotional health status of mothers with PTNBs hospitalized in a neonatal care unit (NICU).

General purpose: To establish the effectiveness of expressive writing in the experience of mothers of hospitalized preterm infants.

Specific objectives:

• Establish the coping capacity of the mothers of the premature Infants before and after the intervention.
• Determine the level of post-traumatic stress of the mothers of the premature Infants before and after the intervention.
• Establish the performance of the maternal role of the mothers of the premature Infants before and after the intervention.
• Describe how mothers of RNPT experience the experience of having their child hospitalized
• Understand the meaning of the mother's experience in the transition to the maternal role of a premature

Design: Mixed study, where the quantitative and qualitative method is used. Which allows to combine the two paradigms to approach in a more integral way to the research problematic. In this sense, the research will be strengthened, to be able to incorporate data from the writing of the participants to give greater meaning to the numerical data. From the quantitative is an experimental study type controlled clinical trial. From the qualitative, it will be interpretative phenomenological; philosophical methodology that allows to discover and understand the meaning of human experience around a phenomenon.

For the measurement of the results before and after the intervention, the Nursing Outcome -NOC: Performance of the maternal role (2211) will be applied to both groups. In the experimental group the Nursing Intervention will be applied- NIC: Journalist (4740)

Population of study: Mothers with premature newborns hospitalized in the neonatal care unit at third level Hospital in Bucaramanga, Colombia.

Sample Size: For the quantitative design, the sample size was calculated taking into account, according to previous studies the change of 2.5 in the PST scale to achieve a decrease in the levels of post-traumatic stress. This study will randomly allocate 60 premature infant´s mothers, 30 for each group, with a power of 80% and an alpha of 0.05. For the qualitative design, convenience sampling will be taken into account from the writings made by the mothers of the intervention group.

Inclusion Criteria: Mothers with:

• Age of 14 or more years old
• Preterm newborns with a gestational age of less than 34 weeks
• Preterm newborns who are hospitalized in the NICU of the Third level Hospital of Santander
• Preterm newborns alive at the time of assignment to the control group or intervention group
• The time of hospitalization of the newborn must be at least one week in the hospital institution.
• Nursing Diagnosis Readiness of enhanced parenting (00164)

Exclusion Criteria:

Mother with

• Limitations like as hearing, motor and / or mental disability - measured through the minimental test.
• Consumption of psychoactive substances
• Mothers who can not read or write
• Newborns with a confirmed diagnosis of severe diseases as a congenital malformations.

Instruments: Coping level scale, Perinatal posttraumatic stress scale, maternal role performance scale, Minimental test

Inclusion Criteria:

Mothers with:

• Age of 14 or more years old
• Preterm newborns with a gestational age of less than 34 weeks
• Preterm newborns who are hospitalized in the NICU of the third level Hospital of Santander
• Preterm newborns alive at the time of assignment to the control group or intervention group
• The time of hospitalization of the newborn must be at least one week at the hospital.
• Nursing Diagnosis Readiness for enhanced parenting (00164)

Exclusion Criteria:

• Limitations as hearing, motor and / or mental disability measured through the minimenta test.
• Active consumption of psychoactive substances
• Mothers who can not read or write,
• Mothers of newborns with a confirmed diagnosis of severe diseases like congenital malformations.

The publication of the results of this study will be carried out in an indexed journal and in scientific events.

random allocation of the mother to the control or intervention group