Introduction:
Only a few studies report the impact of different clinical conditions of preterm infants on parental stress.

Material and methods:
Ninety parents of middle to late preterm infants filled out the parent distress subscale of the Parenting Stress Index-short form when their children were 1 month old. The scores were compared based on five clinical conditions of preterm infants: Condition 1: infants whose disease occurred before or during delivery; Condition 2: infants whose disease occurred after delivery; Condition 3: infants whose mother had a disease that might induce preterm birth or infant morbidity; Condition 4: infants with infectious disease; Condition 5: infants with respiratory distress. Parental distress scores in different demographic and clinical conditions was compared.

Results:
The stress of parents worsen when preterm infants had a disease occurred before and during delivery. In contrast, there was no impact when infant had a disease occurred after delivery. The stress of parents worsened when the preterm infants had respiratory distress. In contrast, there was no impact when infant had an infectious disease. When there was a maternal disease that may induce preterm birth or disease in infants, parental stress would worsen.

Conclusions:
The risk factors mentioned above increased parental stress as early as 1 month after delivery. Finding the risk factor as early as possible, and then performing a nursing intervention is crucial to decrease parents’ stress when they had preterm infants.