Who knows my blood type?

September 24, 2008 4:45 PM

Who knows my blood type?

I don't know my blood type, and I just called my doctor, who has done blood work on me before, and her office staff said they don't have it (!?), and it's not on my driver's license... so who else ought to know?

Or, how can I get tested and how much will it cost and how long will it take? Can I buy a self-test at a US drug store?

(No, Mom didn't remember.)

posted by NortonDC to health & fitness (17 answers total)

If you donate blood, they can tell you. And it's free!
posted by adiabat at 4:51 PM on September 24, 2008 [3 favorites]

Maybe they can even tell you if you sell your plasma. And they'll pay you!
posted by metajc at 5:01 PM on September 24, 2008

Oh, and here's a cool test kit.
posted by metajc at 5:03 PM on September 24, 2008 [3 favorites]

A while ago, I needed to know my blood type, so I called up the hospital at which I was born and asked. I think it only took them a few minutes to find the file, even though I hadn't been at that hospital since my birth. This was in Canada; obviously, YMMV elsewhere.
posted by ssg at 5:26 PM on September 24, 2008

you can get your blood typed at your doctor's office, i think.
posted by thinkingwoman at 5:43 PM on September 24, 2008 [1 favorite]

I'd go the donate blood route, if only because there are some pretty severe blood shortages, especially if you have a rarer blood type as I do (B-). It's an easy process too. Just dunno how long it takes them to type it.
posted by tittergrrl at 6:10 PM on September 24, 2008

The American Red Cross checks your blood type when they screen you before you donate blood.
posted by C17H19NO3 at 6:14 PM on September 24, 2008

Oh, and if I remember correctly they do the test while you are being screened, so it's pretty quick.
posted by C17H19NO3 at 6:15 PM on September 24, 2008

Yes, donating blood is a great way to learn your blood type!

Unless ARC does things very differently from my blood bank, they do not type your blood until after you've donated and it goes to the lab. It doesn't take very long to get the results however. At The Blood Center, you can check online usually about 48 hours after donation to see what your cholesterol level and blood type are.

ssg, you might want to have that result double-checked. Your blood type is not necessarily established at birth, the antibodies (A, B, and/or rh) can form a little bit later. This is why doctors like to use O- blood if they have to give it to a newborn (O- is the "universal donor").
posted by radioamy at 7:00 PM on September 24, 2008 [1 favorite]

Lab Tech here blood type takes about 5 mintues. Give blood or get your doctor to order it. Should run about $40.00.
posted by bjgeiger at 7:02 PM on September 24, 2008 [1 favorite]

When I first gave blood at the Red Cross about a year ago, they sent me a donor card with my blood type listed on it about a week later. It's free, and it helps people, and you get free cookies afterward. Plus, then you have a card to keep in your wallet saying what blood type you are, in case you're prone to forgetting. I had asked my doctor 3 different times and forgotten 3 different times, until I started donating regularly.
posted by vytae at 8:26 PM on September 24, 2008

Why would you even bother to learn your blood type? I am not a haematologist, but as I understand it, in the modern era everytime you get a transfusion your blood is "crossmatched", meaning it is checked against the blood of your donor, for all (or almost all) known blood antigens, including A, B, O and rhesus, but also including a lot of rare stuff. Just because you have a previous test showing you are O +ve your doctor isn't going to immediately transfuse any old O +ve blood.

If in a dire circumstances, such as massive trauma, or some kind of intraoperative disaster, you might get emergency non-crossmatched blood, but it will be O -ve regardless of your blood type.

If you have some very rare combination of antigens, it might be handy to know, but otherwise I think knowing your ABO status is mostly of historical interest.
posted by roofus at 1:31 AM on September 25, 2008

roofus, in cases of dire emergency, there may not be time to crossmatch. Of course if it is that dire, you might not be conscious enough to tell them what type you are...

It is also important to know for traveling. I'm Bneg and can only receive blood from other Bnegs and O negs. In many countries both of these types are hard to come by and being for-warned is for-armed or something like that.
posted by silkygreenbelly at 2:26 AM on September 25, 2008

I guess I didn't explain it clearly enough. In those dire circumstances, when there is no time to crossmatch, in the West you get O -ve regardless of blood type. ERs/labour wards keep a fridge full of it for that purpose. How does knowing you are B -ve forearm you for anything? Would you accept non-crossmatched B -ve blood if you were travelling in the third world in any kind of elective transfusion situation? Either they have the right blood for you or they don't, I can't see how knowing approximately what type you need helps.
posted by roofus at 2:41 AM on September 25, 2008

Well, tittergrrl points out that it's nice to know whether or not your blood type is more urgently needed for donation, although I'm sure that's not what the asker is wondering about.

But knowing your blood type can be useful in other ways beside emergency transfusion situations. I know someone who used knowledge of her blood type to help determine who her father was after the person in question was deceased and paternity couldn't be tested in a more exacting manner. (Blood type is a pretty crude method of geneology, of course, but it can at least rule people out.)
posted by adiabat at 5:33 AM on September 25, 2008

roofus, I want to know my blood type so my wonderful wife can avoid unnecessary shots for potential Rh factor incompatibility while she is pregnant with our little girl!
posted by NortonDC at 5:41 PM on September 25, 2008 [1 favorite]

That's a good reason...but your OBGYN shouldn't pay any notice to what your blood type is. At least 1 in 10 children are unwittingly raised by men who are not their real fathers. In the UK we have to give all the Rhesus -ve mums anti-D regardless of paternal blood type in order to avoid this problem (i.e. the presumptive father is Rhesus -ve, but the postman is Rhesus +ve, and the mother can't admit to this in the antenatal clinic)
posted by roofus at 3:23 AM on September 26, 2008 [1 favorite]