Prenatal maternal stress has been shown to impair birth outcome and behavioral functioning in nonhuman primate offspring. Little is known about the effects of prenatal stress on behavioral development in humans. We assessed the effect of self-reported prenatal stress on behavioral characteristics of 81 newborns using the Neonatal Behavioral Assessment Scale (NBAS). We suspected that high levels of perceived chronic stress during pregnancy may negatively affect the brain development of the fetus, reflected in poorer behavioral maturity and higher irritability. We found a poorer performance of newborns from high stressed mothers in the NBAS.