Maternal antibodies are known to cross the placenta during pregnancy and can be detected in a fetus as early as 13 weeks. By 30 weeks, maternal antibody levels in the fetus are about half that of the mother, and at birth, the concentration is even greater in the newborn than in the mother herself. The maternal antibodies stay in the baby’s bloodstream for about 6 months after birth, after which the baby’s own immune system takes over. Once in the fetal bloodstream, the antibodies then may enter the brain and attack cells that have corresponding proteins that act as antigens. This antigen-antibody response is an important defense against foreign invaders, such as bacteria or viruses, but is not normally directed … Continue reading Maternal antibodies can attack the fetus’ brain cells