Blocking antibodies are a problem of the immune system and if the test is negative, the mother will attack the embryo and cause the fetus to stop. The condition usually occurs before the tenth week of pregnancy and can be treated, while the pregnant woman must cooperate with the treatment. Negative blocking antibodies include anti-mate CD3, CD4 and CD8 antibodies. The absence of any one of these will result in a negative blocking antibody. Medically speaking, if the antibodies are negative, the pregnant woman’s immune system will attack the fetus. If the fetus has no immune protection it will be harmed, stop developing, or even miscarry, which usually occurs before the tenth week of pregnancy. However, even if the test is negative for closed antibodies, pregnant women need to be careful not to worry too much and can follow a reasonable treatment for their specific condition, actively cooperate and regulate their emotions in order to promote overall health.