Maternal stress-induced reduction in birth weight as a marker for adult affective state.

It is known that adverse events experienced by a pregnant woman may be reflected upon the developing fetus and adversely affect its mental wellbeing in later life. In a recent study by our group, prenatal stress was associated with a clear increase in anxiety- and depression-related behavior in male, but not female Sprague-Dawley offspring. Since birth weight data were recorded we were able to determine whether birth weight, as an important outcome measure of fetal distress, may be used as a predictive indicator for adult performance. For this purpose, a correlation analysis was performed, aimed at studying the possible link between stress-induced fetal growth restriction and adult affective state. Male birth weight correlated positively to depression-related behavior in the forced swim test. Furthermore, it weight was correlated negatively to basal, and positively to stress-induced, plasma corticosterone levels in adulthood. Female birth weight did not correlate to any of the studied outcome measures. These data suggest that male birth weight may represent a valuable indicative marker for variations in adult affective state with a developmental origin.