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Name: Shaynie
Status: Student
Age: 17
Location: N/A
Country: N/A
Date: September 2002

I was wondering where the blood comes from when a baby is conceived. I have heard that the bloodline only comes from the father, and that if the mother's blood gets into the umbilical cord when the baby is still attached, that both the mother and the baby could die. I was just wondering if that was true. If you could answer my question and also give me a web site to find out more info, i would greatly appreciate it.

First of all, the baby makes its own blood. Once the baby begins to grow, it forms its own bones, skin, hair, etc. and also begins making blood. The blood type (ie, A, B, AB, or O) is determined by both parents. Type A and Type B are both dominant, which means that if they are there, they will show up. Type O blood is recessive, which means that both parents have to give the baby an O type gene for it to have type O blood. If the baby gets and O gene from one parent and a B gene from the other, it will have type B blood and the O is "hidden". If one gives a B and the other an A the baby will be type AB. Anyway, no blood passes through the umbilical cord. Only nutrients and oxygen are small enough to pass through the filters in the cord.

However, during birth, the placenta detaches from the womb and some bleeding occurs. Only at this time can blood from the BABY get into the mother's blood stream. If the baby has a different blood type than the mother, she will make antibodies to the baby's blood. So there is usually no problem during the first pregnancy. NEXT time she gets pregnant, if the baby is a different blood type than the mother, the antibodies that she made during the first birth can cross the umbilical cord into the baby (because they are small enough) and hurt the baby. But there are shots that can be given during the first birth that can "suck up" all the baby's blood cells so that the mother does not make antibodies to them. The only time something could happen to the first baby is if the placenta detaches partially and some bleeding is going on, but not enough to cause miscarriage. This is rare.


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