More than 20% of all pregnant women suffer from antenatal depression which can be due to several factors including social, psychological and biological factors. A new study reported that a woman’s mental health during pregnancy can directly influence the developing child’s immune system.

The researchers at the University of Alberta examined the health records of over 1,000 mother-infant pairs who participated in the CHILD cohort study which is following the health of thousands of Canadian children in their teens. The mothers had to fill out regular questionnaires about their mood throughout their pregnancies.

"Our study shows that what happens to the mother during pregnancy could affect the levels and function of the cells that produce immunoglobulin in children," Sify quoted Anita Kozyrskyj, a pediatric epidemiologist and a leading researcher on gut microbes.

The researchers collected stool samples from the infants in order to examine the presence of intestinal secretory immunoglobulin A (sIgA), an antibody that plays a crucial role in immune responses.

"This immunoglobulin is really important in the microbiome for developing oral tolerance to environmental antigens," Sify quoted the study’s lead investigator Liane Kang.

The key findings of the study:

  • Mothers who experienced depression symptoms during the final trimester or persistently before and after giving birth were two times more likely to have children with extremely low levels of immunoglobulin A in their gut
  • There wasn’t any link found between postpartum depression and maternal depressive symptoms.
  • The depression symptoms experienced by mothers did not have to be severe enough for a clinical diagnosis
  • Lowered immunity could put the babies at risk for respiratory or gastrointestinal infections including allergies, asthma and higher risk for other health conditions including diabetes, autoimmune diseases, obesity, and depression.

The study demonstrated that depressed mothers could transfer higher levels of the stress hormone ‘cortisol’ to their developing fetuses. This could interfere with the production of cells that create immunoglobulin after birth. The researchers opined that further research is required to understand the link between maternal microbiome and infant immune development. The study also highlighted the need for mental health supports for women during pregnancy.