If I, as the mother, and both of my children are negatives does that mean my husband is likely to be as well?  I know his blood type but not his RH factor and wondered if you could determine it from the above information.

Thanks!  

rh is recessive

hub could be either one.....get a bloodtyping kit to make sure

Quoted from aisling

If I, as the mother, and both of my children are negatives does that mean my husband is likely to be as well?  I know his blood type but not his RH factor and wondered if you could determine it from the above information.

Thanks!  

It only means that hub has at least 1 Rh(-) allele, but he could have either another (-) allele, making him Rh(-) or the (+) allele making him Rh(+).

If you consider the laws of probability, your husband probably is also RH-. About 15% of the population is RH-, so if he is RH+, the chances of 2 consecutive children being RH- is not likely to happen.

Think of it like this. If you have a bag of 7 marbles, 5 blue and 2 red, and you have to pull out one at a time without looking, what are the odds the first 2 marbles would be the red ones? Certainly not impossible, but not terribly likely.

Sorry if that's a juvenile example but I"m a home school mom and that's how my brain works.

I'd recommend he buy a bloodtype kit also to get tested.

Quoted from Adopted4

If you consider the laws of probability, your husband probably is also RH-. About 15% of the population is RH-, so if he is RH+, the chances of 2 consecutive children being RH- is not likely to happen.

Actually, if he is Rh+ with an Rh- reccessive available to pass on, the odds of two out of two children being Rh- is 25%. That is fairly significant.

Think of it this way. If the first child was Rh+ and the second was Rh-, if they had a third child the odds would be 50:50 either way on the next child, so in that particular case "the odds of two consectutive children Rh-" is a coin toss. It's all how the problem is framed.

Thanks everyone!  Colleen, we are also homeschoolers!  

How important is it for hubby to know his RH factor if I know his bloodtype?  Can I figure his genotype without it with a reasonable degree of certainty?

The RH factor is not relevant to the blood type diet, but is most certainly necessary to know for determining genotype. It's nice you can test him at home if you're anything like our family and don't want to make a trip to the doctor for that one thing. It's very easy to do. Even our newly adopted youngest daughter who was traumatized by any kind of needle did very well getting her finger pricked to determine her blood type. Of course, her watching her siblings do the tests before her certainly motivated her to do it.

O.K. time to get off the computer to make dinner.

If you use the basic or intermediate calculator to determine GenoType, Rh is never necessary. If you use the advanced calculator, Rh is sometimes needed and sometimes not needed.

Quoted from aisling

How important is it for hubby to know his RH factor if I know his bloodtype?

If you are planning on having more children, I would consider it quite important. I would expect some medical practitioner to have already tested his blood type, if they knew you were rh negative and were either marrying or expecting.


If you cannot get a medical practitioner to tell you what his Rh factor is you can determine Rh by donating blood or with an Eldoncard.

http://www.4yourtype.com/prodinfo.asp?number=YTE001