RESUMEN
OBJECTIVE: To evaluate whether the markers of autonomic nervous system activity, dopamine beta-hydroxylase (DBH), chromogranin A (CGA) and met-enkephalin (E), are different in cord blood from neonates born after conditions associated with chronic intrauterine stress (CIUS) as compared to neonates born after a normal pregnancy. STUDY DESIGN: 61 newborns (median BW 2,840 g, range 617-4270 g) born after a pregnancy complicated by maternal hypertension, maternal smoking, maternal diabetes mellitus or intrauterine growth retardation (STR group) were compared with 88 neonates (median BW 2,910 g, range 4,00-4,370 g) who had not suffered from such intrauterine conditions. DBH, CGA and E were measured in the cord blood of both groups. RESULTS: When both groups were taken together, high DBH values were best related to maternal smoking (p = 0.004) and low E levels to maternal diabetes (p = 0.02). Within the STR group, high DBH values were best related with all conditions linked with CIUS (p = 0.008), E levels were best linked with the combination of intrauterine growth retardation (positive correlation) and maternal diabetes (negative correlation) (p = 0.03). For CGA there was only a weak positive relation with maternal smoking (p = 0.3). CONCLUSION: Certain intrauterine conditions associated with CIUS, especially maternal smoking, may lead to alterations of the autonomic nervous system as revealed by some of its markers in cord blood of neonates. This may be important in the pathogenesis of certain conditions after birth, such as the sudden infant death syndrome.