Is 'pregnancy brain' real? This is the reason for the phenomenon

A new study has found a biological explanation for the phenomenon of 'pregnancy brain': a direct link between high estrogen levels and changes in brain activity. Experiments in mice identified a brain mechanism, and a study of 70 women showed a link between high estrogen levels and lower memory scores in the second and third trimesters.

A new study offers a biological explanation for the phenomenon of 'pregnancy brain', the forgetfulness and confusion many women report during pregnancy. Researchers found a direct link between high levels of the hormone estrogen and temporary changes in brain activity affecting memory. In experiments on mice, injecting estrogen at levels similar to late pregnancy caused difficulty in recognizing familiar objects and remembering locations. The identified mechanism is overactivation of neurons in the hypothalamus, which 'silence' activity in the hippocampus, the brain's memory center. Artificially turning off these cells restored memory to normal function. In another study involving 70 women, half of whom were pregnant, women with higher estrogen levels scored lower on memory tests, especially in the second and third trimesters, even after controlling for variables like sleep quality and mood. The researchers emphasize that the study in women shows a statistical link (correlation) rather than direct causation, but identifying the brain circuit in mice lends scientific validity to the phenomenon.