You are right about the shot but not always does the mother with rh neg have the shot.. The negative rh is less likely to be compatible with the fathers. So therefore the father needs to be checked. If he is also negative the mother needs the shot or the baby will die. If his blood type will mix with hers and he’s positive the couple won’t have to worry about the mothers rh. This is the reason couples had to have a blood (both) in the 50s and 60s to avoid rh incompatibility. If the mother is rh positive there is no need to check the father. Just l I me magnets. To positives will attract. A pos and neg attract. To neg not only don’t attract, but repelled.


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