Preterm birth may be a larger risk factor for increased blood pressure than intrauterine growth restriction

Aim Very low birthweight ( VLBW ) and prematurity have been associated with an increased risk of high blood pressure ( BP ). We compared BP and salivary cortisol responses to a stressful situation between adolescents with a VLBW and controls. Methods We compared three groups aged 12–17 years: 30 born VLBW but appropriate for gestational age ( AGA ) at a mean of 27 weeks, 19 born VLBW but small for gestational age ( SGA ) at a mean of 31 weeks and 43 term‐born AGA controls. Three consecutive BP measurements were performed before a magnetic resonance imaging ( MRI ) examination. Salivary cortisol and perceived stress were assessed before and after the MRI . Results Systolic and diastolic BP decreased significantly for each repeated measurement in the VLBW ‐ SGA group and controls, but remained unchanged in the VLBW ‐ AGA group. The third systolic BP measurement was 9–12 mmHg higher in the VLBW ‐ AGA group than the other groups (p < 0.05). There were no differences in salivary cortisol between the groups, before and after the MRI or between the sexes. Conclusion Dynamic BP responses differed between adolescents born VLBW ‐ AGA and the other groups, indicating that extremely preterm birth may be a larger risk factor for increased BP than intrauterine growth restriction.