Context: Animal data suggest that adverse early experiences may affect endocrine and immune functioning in later life.

Objective: To assess the impact of preterm delivery on HPA axis functioning, heart rate responses and immune function.

Participants: Former preterm children, aged 8-14 years (n=16); sex and age matched full-term born control children (n=16); data on birth weight, gestational age, birth weight for gestational age (in SD units), acutal body weight, height and body mass index were assessed.

Design and outcome measures: Subjects were exposed to a standardized laboratory stressor (TSST-C). Cortisol in saliva was determined in ten minutes intervals before and after the stress test; heart rates were obtained continuously during the stress test. Additional assessment of saliva cortisol (a) on three consecutive days after awakening, and +10, +20, and +30 minutes (morning cortisol) and (b) on 8:00 AM, 2:00 PM, 4:00 PM and 8:00 PM (short diurnal profile). Measurement of the DTH reaction to seven recall antigens (Multitest^®CMI).

Results: Exposure to the TSST-C yielded in significantly increased cortisol levels (F(8,232)=19.86; p<.001) and heart rates (F(38,988)=10.46; p<.001), however, no difference between former preterms and full-terms could be observed. No between-group differences were found in the short diurnal cortisol profile. Former preterms showed significantly higher CORT levels after awakening (F(3,102)=3.14; p<.05). Additionally, a significantly suppressed DTH response (reduced number of positive antigens (t=-2.64, p<.05); induration (t=-2.4; p<.05)) was found in former preterms.

Conclusions: The data suggest that preterm delivery may be associated with altered endocrine and immune functions well into late childhood.