Increased symptoms of illness following prenatal stress: Can it be prevented by fluoxetine?

• Prenatal stress augmented endotoxin-induced symptoms of illness in mice.
• Prenatal fluoxetine reversed the effect of prenatal stress on sucrose consumption.
• Prenatal fluoxetine augmented the effect of prenatal stress on body weight loss.
• The effects of prenatal stress and prenatal fluoxetine were sex-dependent.

Stress during pregnancy is associated with lifetime negative consequences for the offspring. The present study examined the effects of prenatal stress on symptoms of illness following an immune challenge in mice. Additionally, this study examined whether pretreatment with fluoxetine (FLX) could prevent the effects of maternal stress on illness symptoms. Mice prenatally exposed to stress, with or without FLX were administered with saline or endotoxin. In males, prenatal stress significantly augmented endotoxin-induced body-weight loss and reduced food consumption; prenatal FLX did not prevent these responses, and, in many cases, augmented them. In females, prenatal stress worsened endotoxin-induced suppression of sucrose intake, and prenatal FLX reversed this effect. These findings provide the first indication of altered response to an immune challenge following prenatal stress and selective serotonin reuptake inhibitor (SSRI) treatment. These results may have implications for health and well-being of offspring exposed to stress during pregnancy.