RESUMEN
BACKGROUND: Mothers of premature infants experience a high level of stress. The current study was conducted aiming at investigating the impact of maternity support program on the stress of mothers in the first encounter with infants. METHODS: This experimental study began in neonatal intensive care units (NICUs) of two hospitals of Tehran; that is, Mahdieh (intervention) and Shahid Akbar-Abadi (control), from Feb 14, 2016, to May 14, 2016. Both are educational and referral centers including three levels of NICU that were randomly allocated to intervention and control sites. In the span of study period all 75 infants and mothers with inclusion/exclusion criteria in the Mahdieh hospital were included in the intervention group and vis-à -vis all 68 infants and mothers in Shahid-Akbar-Abadi were enrolled in the control group. The designed intervention was conducted based on the support system pattern of mothers with premature infants in the interventional group. In the first stage of intervention, in the intervention group, mothers were provided informational, emotional, and spiritual support before and during the first exposure and were empowered for comfortable interactions. The control group received routine care. After the first exposure, the mothers' stress was measured by the Parental Stressor Scale: Neonatal Intensive Care Unit (PSS: NICU). The data were analyzed by STATA software as well as t-test, Chi-square, and average treatment effects (ATEs) were estimated using inverse probability treatment weights (IPTW). RESULTS: After adjusting pre-treatment variables by IPTW, the adjusted average difference in the stress score over the NICU environment, infant's behavior and appearance, the special treatments on him/her, and the change in the parental role and total stress were 1.47 (1.19-1.75), 1.06 (0.73-1.14), 1.21 (0.93-1.49), and 1.18 (0.93-1.44), which were lower than the control group (P < 0.001). CONCLUSIONS: The intervention reduced significantly the stress of mothers. The policy-makers are suggested to conduct this method.