According to a study published in the journal Brain, Behavior, and Immunity, pregnant women with anxiety have an immune system that differs biologically from pregnant women without anxiety. The study showed that cytotoxic T cells, an immune system component that hunts down sick or otherwise harmed body cells, are more prevalent in pregnant women who feel anxious.

The researchers stated that the blood-circulating immunological markers showed distinct behaviour in stressed women. This study is the first to examine how worry impacts how the immune system changes during pregnancy and after giving birth.

Principal investigator Dr. Lauren M. stated that women with anxiety appear to have an immune system that behaves differently from that of healthy women during pregnancy and after delivery. The findings of the study showed that in women with anxiety, levels of cytotoxic T cells were elevated during pregnancy and then decreased in the weeks following childbirth. On the other hand, in women without anxiety, the activity of these cells declined in pregnancy and continued to decline after birth.

The researchers also found that in women with anxiety, the activity of primarily pro-inflammatory cytokines was repressed throughout pregnancy and subsequently increased after delivery, whereas healthy women showed the reverse pattern. Hence, the researchers concluded that the activity of the immune system of a pregnant woman varied based on her levels of anxiety. 

(Source: https://theprint.in/health/study-discover-pregnant-women-with-anxiety-have-biologically-different-immune-systems/1414382/ )