If a Rh-negative woman and a Rh-positive man have a child, the fetus may haveRh-positive blood inherited from the father. (Approximately half of children born to a Rh-negative mother and a Rh-positive father are Rh-positive.)
If this is the mother's first pregnancy, Rh incompatibility is usually not an issue.
This is due to the fact that the baby's blood does not normally enter the mother's circulatory system during pregnancy.
However, during the birth, the mother's and baby's blood can mix. If this occurs, the Rh protein is recognized as a foreign substance by the mother's body.
It may then begin producing antibodies (proteins that act as defenses against foreign cells) against the Rh protein.
Rh-negative pregnant women may be exposed to the Rh protein, which may cause antibody production in other ways as well.
Combustion is the burning of a substance. It could be complete or could be incomplete. It changes the form of carbon and so it plays it's role in cycle