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What is RH test ?
It is a blood test by which the blood type is determined, if RH is positive or negative
Who should perform the examination and when?
The couple perform this test to avoid complications for the baby during pregnancy and after childbirth. It is best to perform the examination during planning for pregnancy
When does a woman need an injection?
If the mother's blood type is RH negative and the father's one is RH positive, the injection should be taken
Note: There is no problem if the parents are negative or positive, but the problem presents if the father is positive and the mother is negative. That's because there is a possibility that the baby will be positive like his/her father
Why is the injection given?
When the blood of the fetus is positive like the father, and the positive is usually the dominant feature. During childbearth the mother’s blood may mix with the child’s blood, so her body begins to form antibodies that will fight the baby in the next pregnancy, which may cause miscarriage. That is why it must be taken immediately after birth to prevent antibodies formation by the mother's body 
Is the injection taken after every birth?
Yes, the mother with a negative RH needs to take the injection after every birth or abortion
Does the injection affect the fetus?
No, it has no effect on the fetus. Rather, it is given to protect the fetus from complications