Final answer:
It is false that a neonate with severe fetal anemia cannot be cross matched prior to birth. The condition known as hemolytic disease of the newborn is mainly problematic in second or subsequent pregnancies due to the possible development of maternal anti-Rh antibodies during the first delivery. The issue can be largely prevented with the administration of Rho(D) immune globulin.
Step-by-step explanation:
Hemolytic Disease of the Newborn and Fetal Anemia
It is false that you can't cross match a neonate diagnosed with severe fetal anemia prior to birth. In the context of hemolytic disease of the newborn, also known as erythroblastosis fetalis, the disease often becomes a problem during the second or subsequent pregnancies. Hemolytic disease of the newborn is primarily due to the Rh incompatibility between an Rh-negative mother and an Rh-positive fetus, which can lead to the mother's immune system producing antibodies against the fetus' Rh-positive red blood cells. During the first pregnancy, fetal and maternal blood are less likely to mix, so the Rh-negative mother does not commonly produce antibodies against Rh antigen then. However, during the delivery of the first child, fetal red blood cells may enter the mother's circulation. This exposure may lead her immune system to produce anti-Rh antibodies.
When the mother becomes pregnant again with an Rh-positive child, these previously formed antibodies can cross the placenta and cause destruction of the fetal red blood cells. This leads to hemolytic disease of the newborn in the fetus, which may result in anemia, amongst other complications. Prevention of this condition is possible by administering Rho(D) immune globulin, which helps to prevent the formation of anti-D antibodies in the mother.
The myth that a person's nutritional needs can be determined by their ABO blood type is not supported by scientific evidence.
Red Blood Cell Destruction and Pregnancy
In the context of pregnancy, maternal and fetal blood does not typically commingle in a way that would cause the pregnant person to produce anti-Rh antibodies against the first Rh-positive fetus. Only during childbirth or if there is a breakage of the fetal-maternal barrier, such as the embryonic chorion, do fetal blood cells potentially enter the maternal circulation, which may trigger the immune response leading to hemolytic disease in subsequent pregnancies.