Question about kid/parent blood type?

Question

I have 2 kids. My blood type is B+, their father's is O+. I was told in the hospital that my firstborn's blood type was B+, second is O+. Now my firstborn is 17 and gave blood for the first time, got his card back and it says he's O+. Does anyone know how this could've happened? If a mistake was made, is it more likely when he was a newborn in the hospital?

I suppose it's a stupid thing to be sad about but I was always glad he shared my blood type. :-(

Any science types who have the patience for a silly question like this, it is appreciated.

A few conflicting answers, how will I ever choose a favorite? If you really know (like you learned it because you're a scientist or lab tech or teacher or something), say so. If the poster who claims all kids have their father's blood type (Rh factor optional) I will feel better. Perhaps they just told me his blood type was mine because they tell all new moms that so they'll shut their yaps, as another poster suggested. I hate the medical establishment.

Answer 1

The tests they do in blood drives are often wrong when the person involved is not homozygous for one particular blood type (ie if he is B+ because because he got a B from you and an O from your husband). I can't explain why; the tests are very similar (blood drives do often rely on student labor). My blood type has been read wrong when giving blood as well (I am A+, but get read as A's sometimes and O sometimes.)

Its worth getting retested just to be sure. In the off chance your son needs to go to the hospital and receive blood, B+ can accept B or O. O can only accept from other O's.

Answer 2

its an interesting question and there seem to be many answers, most likely there was an error at the hospital...

Also, I am AB- my mom is A+ my dad is b-
My son is 0+, his father is b+

so there are clearly things differences

here is an excerpt about blood type to clear up some facts from a website on childrens health:

I often get questions about a new baby's blood type. For example, a baby who is A- might be born to two parents who are both A+ and they are wondering how that could happen.

Although many people understand how the major blood groups are inherited, the Rh factor (the + or - sign after the blood type) is more confusing.

To begin with, you normally have two alleles (out of a possible three alleles - A, B, O) for your blood type and pass one of them to your child.

A person who has a type A blood type can have either two A alleles (AA) or they can have one A and one O (AO). The same for someone of blood type B, who can be either BB or BO.

If you are type O, then you will pass an O allele to your child because you must be OO. If you are AB, you can pass either the A or the B to your child.

For parents who are both type A, they can both be either AO or AA. Therefore, they could pass an A or an O to their child and they could have a child with either type A blood or type O blood. This child could not be type B or type AB.

Just like you have two copies of the A, B or O alleles, you also have two copies of the Rh factor alleles. So for two parents who are both Rh positive, they could be either +/ - or +/+. If both of them are +/-, then they could have each passed the - allele to their child and have a negative (-/-) child.

So two A+ parents could have children with the following blood types:

A+, A-, O+, O-

How about if one parent was A- and the other was A+?

Again, the baby could be either A+, A-, O+, O-. While the A- parent would only give an Rh- factor, the other parent could donate either a + or a - depending on whether he was -/+ or +/+.

What if they were both A-?

Then their baby could only be either A- or O-, since both parents are Rh - they must be -/- and can only give a - to their child. This child could not be A+ or O+ with two parents that are A-.

How about if mom is A+ and dad is B+?

In this case, mom could be either AA or AO and have either +/+ or +/- Rh factor alleles. So she could give her baby either an A or O allele and either a + or - Rh factor allele.

Dad could be either BB or BO and will also have either +/+ or +/- Rh factor alleles, and could give his baby either a B or O allele and either a + or - Rh factor allele.

So the baby could be either:

AB : getting A from mom and B from dad
A (AO) : getting A from mom and O from dad
B (BO) : getting O from mom and B from dad
O (OO) : getting O from mom and O from dad
And his Rh factor could be either + or -, depending on which Rh factor allele he inherits from each parent. So this baby could have any of the possible blood types.

With newer DNA testing, using blood types to determine paternity, or who the father is, isn't really that useful anymore. The main problem is that this method just tells you what the blood type the father could or could not have, and since many of these blood types are common, it doesn't necessarily help narrow down who the father could be.

Still, it sometimes does come up when a baby's blood type isn't what the parents expect it to be.

Answer 3

The only time one has to be concerned when it comes to blood types is when one parent is positive and the other is negative (the letter of the alphabet makes little or no difference). If the father is positive and the mother is negative there is a chance that the baby will have postive blood type and when the baby reaches the birth canal antibodies in the mother's blood will defend HER body against the "intruder" blood type and cause sometimes MAJOR complications for the baby which could include the need to transfuse blood back into the baby. THAT is the reason some states require blood tests be done before a couple marries this way they are aware of the difference before they have a family and the woman can have the RH shot and both parents can possibly "store" blood just in case.

Answer 4

I twas probably a mistake back when he was born. I doubt they made the mistake at this stage. It's good that he is O because he is a universal donor which means he can give to any one that needs blood and they are always asking for type O i have orh negative. My firstborn could have been born a blue baby where they have to transfuse but luckily she wasn't then I had to have a certain shot within so many hours of her being born so future children would not be born blue. Very strange. Just be glas that he has good blood. i also have a disorder found by routine bld. work. my body makes too many platelets. I can't have simple things wrong with me it's always something strange. No one in the medical field told you anything in error on purpose...that is not right for anyone to say that, I am in the medical field and we don't do that.

Answer 5

Most of the answers are helpfully suggesting that you just have him re-tested, but I wanted to weigh in because of all the dumb answers that I read.

The baby DOES NOT always get the father's blood type, not does the first born ALWAYS get the mother's. The hospital would not (should not, at least) just assume that your child shares the same blood type as you, because if someone with rH- blood is given rH+ blood in a transfusion, the body will create antibodies to attack the rH protein, and make you sick.

I am A-, so I had to have RhoGam shots during my preganncy, and when my son was born, his blood was tested right away, because if his type was +, I'd have to get more shots. His turned out to be the same as mine.

My fiance and I just got our cards back from giving blood too, and my blood type was listed correctly. His was listed as A+, and that was the first time it was tested.

It's impossible for me to say which one, the hospital or the blood bank, did the mix-up, but for sure one of them did. I'd just ask for it to be tested again at his next doctor's appointment.

And are you sure you're not mixing it up yourself? Maybe it was the second one that was B+? Probably not, though. Mom's tend to remember things like that!

Answer 6

I am O+ and my husband is A+ and our son is O+. I too had always thought that a child had the father's blood type, but I honestly don't know either. I am thinking of having my son's type done again to see if there was a mix up at the hospital. I hope that someone helps you out!

Answer 7

I bet the hospital made a mistake. When I had my baby at the hospital and asked what blood type my son, first born, was, the doctor just asked me what mine was and said whatever mine is, it will be my son's. No blood test was done or anything. Now I dno't know if the first born always share the same type as the mom. My dumb doctor seemed to think so. Now that I know it is possible for my son not to have the same blood type as mine. I am getting him tested just to make sure. I was so drugged up to believe the dumb doctor. It is good to know the type so if anything happens, it will be a great help for my son.

Answer 8

Dont worry there is nothing to worry about. You may be BO+ where O is a silent gene, and your husband may be a double OO+.
So all the kids have O+. That is because the chances are 3 to 1 that they will be O+ !
The explanation is that you both have inherited two genes from each of your parents. One is dominant the other recessive. That would be BO+ for you.Your husband may have inherited two group O+ genes (OO+)
Ergo- your children will get one gene from each one of you, and managed to get the O's

Why? 45% of the population is O+ (universal donor) 43% is A+, whereas B+ is about 30% or less

Answer 9

Blood types can come any one in your faimly line, when I was first born they told my parents that I was A+ recently I had It checked for a blood that I was going to need during an Up coming Surgery. They tested it and told me I was B- and I was basicly sol. Any ways, neither my mom or my father have had B- blood Mom = O+ father = B+. But my grandmother on my mom side Had B-. so Basicicly genetics is screwy and gives me a head acke

Answer 10

I totally understand about being sad somethig special espically the first born it made you feel like you 2 were closer more alike but I'd say someone looked at your blood type and got mixed up just a clerical error cause your blood doesnt change