Functional Connectivity to the Amygdala in the Neonate Is Impacted by the Maternal Anxiety Level During Pregnancy

Anxiety during pregnancy is common, and exposure to heightened anxiety during pregnancy may influence children's brain development and functioning. However, it is unclear if exposure to low levels of anxiety in utero would also impact the developing brain. The current prospective and longitudinal study included 40 healthy pregnant women without pregnancy complications or previous diagnosis of anxiety disorders.

Pregnant women's anxiety symptoms were measured at 12, 24, and 36 weeks of gestation. Their healthy, full-term offspring underwent a brain MRI scan without sedation, including resting-state functional MRI, at 2 weeks postnatal age. The associations between neonatal brain cortical functional connectivity originating from the amygdala and maternal prenatal anxiety symptom scores were examined using correlational analyses.

Significant correlations were identified after controlling for child sex, postmenstrual age at MRI, and mother's depression symptom scores. Higher maternal anxiety during pregnancy was related to alterations in offspring's functional connectivity between the amygdala and other brain regions involved in fear learning. Specifically, higher maternal prenatal anxiety during the first trimester of pregnancy was associated with lower connectivity between the amygdala and fusiform gyrus and higher connectivity between the amygdala and thalamus. Higher maternal prenatal anxiety during the third trimester was also associated with lower connectivity between the amygdala and fusiform gyrus.

The findings from this study indicate that exposure to low levels of anxiety in utero may also impact offspring brain development and functioning, particularly brain regions that are important for threat detection.