The placenta could be the surprising reason why so many women get autoimmune diseases – even in women who have never been pregnant. Women are diagnosed with 80% of all autoimmune diseases in the U.S. Humans in hunter-gatherer communities have an average of 8 to 12 children – a stark contrast to today’s U.S. average, which is less than 2 children. During these years of childbearing, the placenta sends signals to the immune system to weaken in order to prevent rejection of the fetus. This constant weakening of immunity could be dangerous for the mother, so it’s hypothesized that other aspects of the female immune system are programmed to ramp up during adulthood to compensate (women actually contain more immunity genes than men, possibly for this very reason). It’s possible that because our bodies have evolved to bear such large numbers of children over hundreds of thousands of years, the…
