Antenatal hypoxia and low IQ values
R. L. Naeye and E. C. Peters
We undertook analyses to determine if fetal, intrapartum, and neonatal
hypoxia are important causes of low IQ values. We analyzed prospectively
collected pregnancy, perinatal, and subsequent developmental data for
19,117 children. As expected, sociohereditary and demographic factors had a
large influence on IQ scores. Taking these latter influences into
consideration, nothing that happened during labor, delivery, or the
neonatal period affected subsequent IQ values. The same was true for early
pregnancy disorders that can produce acute fetal hypoxia. By contrast,
antenatal disorders and conditions that can produce subacute or chronic
fetal hypoxia correlated with low IQ values. These antenatal disorders and
conditions were maternal gestational anemia, relative gestational
hypotension, hypertension, multiple births, and fetal growth retardation.
All of these findings were the same whether neurologic abnormalities were
absent or present, suggesting that the same factors were sometimes involved
in the genesis of cognitive impairments and neurologic abnormalities.
