Association between neonatal blood pressure and umbilical cord insulin concentration

The aetiology of the metabolic syndrome remains unknown. This study investigated whether two components of this syndrome, higher blood pressure and higher plasma insulin concentrations, are related at birth. Neonates in the study were from 23 European, 25 Maori, 22 South Asian, and 25 Pacific Islands women having normal singleton pregnancies as well as 6 Maori, 5 Indian, and 19 Pacific Islands women with gestational diabetes (diagnosed by a 3 h 100 g oral glucose tolerance test at 28-32 weeks). Additional fasting glucose and fructosamine concentrations were measured at 36-38 weeks. Umbilical cord blood was taken for insulin, C-peptide, fructosamine and insulin-like growth factor I. Neonatal anthropometry and blood pressure were measured 24 h after delivery. Compared with those with a lower systolic blood pressure (SBP), neonates with a higher SBP had higher umbilical cord insulin (45.6 (39.6-52.8) vs 63.0 (54.6-72.6) pM, p < 0.01), C-peptide (0.22 (0.20-0.25) vs 0.28 (0.26-0.30) nmol l^-1, p < 0.001) and fructosamine concentrations, higher maternal fructosamine concentrations and heavier placentas. These data suggest that neonatal hyperinsulinaemia, possibly driven by minor elevations in maternal glycaemia, may be linked to a higher neonatal SBP.