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SKara
05-11-2014, 11:47 PM
Hi,:)

Does anyone know how much blood an average teenager can donate every month, that is, if they actually can donate every month without risking their health. I have to use the information in my young adult book.

Thanks in advance.

wendymarlowe
05-12-2014, 12:01 AM
Is this for medical reasons (i.e. they have an upcoming surgery and need to bank blood ahead of time), or to donate to other people?

At least in the US, you have to be 18 to donate.

sheadakota
05-12-2014, 12:03 AM
Is this for medical reasons (i.e. they have an upcoming surgery and need to bank blood ahead of time), or to donate to other people?

At least in the US, you have to be 18 to donate.

Nope- you can be 16 with parental consent. you can donate blood every 56 days- they take 1 unit when you do which is roughly around 1 pint.

Lauram6123
05-12-2014, 12:05 AM
I got this from the Red Cross website:

You must wait at least eight weeks (56 days) between donations of whole blood and 16 weeks (112 days) between double red cell donations. Regulations are different for those giving blood for themselves (autologous donors).

Bolero
05-12-2014, 12:08 AM
It is also dependent on body weight. A 5 feet 2 inches adult friend of mine gave blood - and it was allowed because she was just over the minimum weight. Don't know what that is.
She fainted when she got up.

What hadn't been calculated was that she was overweight for her height, so the proportion of blood taken was a bit high.

sheadakota
05-12-2014, 12:23 AM
It is also dependent on body weight. A 5 feet 2 inches adult friend of mine gave blood - and it was allowed because she was just over the minimum weight. Don't know what that is.
She fainted when she got up.

What hadn't been calculated was that she was overweight for her height, so the proportion of blood taken was a bit high.

for the USA for the American Red Cross ( this differs slightly from state to state) you need to be at least 5'1" and weight at least 110lbs.

it does not matter if you are over weight for your height- that is not what made her faint- your body must produce enough blood via capillaries to supply your whole body with blood- extra fat and all- so she had the blood to spare- her blood sugar was either low- or she sat up too fast - or she had a vago-vasil response to giving blood-meaning she was squeamish and well, fainted :) or a host of other reason for why she fainted after giving blood- but being overweight for her height was not one of them. (Shea- who has worked on many a red cross blood drive)

Bolero
05-12-2014, 12:28 AM
Interesting. Thanks.

melindamusil
05-12-2014, 02:40 AM
IIRC the average human adult body has about 8-10 pints of blood. This would vary based on weight and height. For a teenager, I'd assume they are not at their full height/weight yet, so it's probably more like 6-8 pints total.

Since it takes 8 weeks for the body to regenerate that lost pint of blood, if your teenager donates a pint every month, I would bet that he would be at high risk for anemia.

In a DIRE situation, I would guess that he could donate maybe 2 pints of blood, monthly, for 2-3 months max. At 2 pints I would bet he would feel the effects (dizziness, low blood sugar) even after the first donation, and after the 2nd or 3rd he is really going to be struggling. I cannot imagine an ethical medical professional taking that much blood, that often, outside of a really catastrophic situation.

If the OP could provide a few more details, perhaps we can help get this figured out...

RightHoJeeves
05-12-2014, 08:53 AM
I've donated blood 8 or 9 times, and they only took about 1 litre of blood. I have to wait 3 months before doing it again.

franky_s
05-12-2014, 01:22 PM
If you're donating whole blood then as mentioned above, you can only donate every 12 weeks. There are other options though:
You can donate around 800mL of plasma every 2 weeks. It's a much more involved process and not everyone can do it - you need wide veins.
Platelets are every 2-4 weeks. I don't know anything about this process but I'm sure you can google it.

SKara
05-12-2014, 02:36 PM
Thank you all for your replies!

My teenage protagonist does not willingly donate blood. Someone needs her blood and sort of compels her (in the vampire sense, though my book does not contain vampires) to donate blood and then makes her forget it. So the age limit should not be a problem.

From your replies, I was wondering maybe my protagonist (16 years old) could donate a pint of blood every two months. In that case, she wouldn't be aware of it, right? She wouldn't know that someone is secretly doing it to her?

Cathy C
05-12-2014, 02:42 PM
Make sure you plan a method for the hole to disappear in the text. The blood has to leave the body somehow and unless she's a drug user, someone is going to notice the recurring holes in her.

EMaree
05-12-2014, 03:48 PM
From your replies, I was wondering maybe my protagonist (16 years old) could donate a pint of blood every two months. In that case, she wouldn't be aware of it, right? She wouldn't know that someone is secretly doing it to her?

They'd have to be very skilled at taken blood, possibly with some supernatural aide if that fits your story. Even if the blood is taken from somewhere out of sight (back of thigh, maybe? Are there easy veins there? They'd have to vary up the spot they use as well...) there'd be a risk of vein collapse & bruising which would draw the MC's attention to the spot.

She'd also need to be having a balance diet with a lot of iron in it. If she's unaware that she's losing blood and is very active, a vegetarian, or just a light eater, she could easily dip into anemia.

If possible, I'd mention that the MC's mum is a regular donor (maybe MC needed a transfusion to survive when she was born and her mum's been a regular donor ever since to "pay it forward") which would hint that your MC has good veins for donating.

SKara, if you haven't donated blood before you could donate at a local blood drive for research. :)

SKara
05-12-2014, 04:39 PM
Make sure you plan a method for the hole to disappear in the text. The blood has to leave the body somehow and unless she's a drug user, someone is going to notice the recurring holes in her.

Thanks. Maybe I could use the holes to hint to her that she has some memory gaps, because finally she has to realize the secret happenings somehow and try to find out the person.

SKara
05-12-2014, 04:42 PM
there'd be a risk of vein collapse & bruising which would draw the MC's attention to the spot.

I hope the bruising won't appear until the third or fourth time?

Maryn
05-12-2014, 05:59 PM
Not everyone bruises, and those who do don't bruise every time. Other than the puncture wound near a vein, I can never detect any difference in the way I feel or look, including the donation site at my inner elbow, after I give blood. It's perfectly plausible to have her feel utterly normal but wonder about the needle mark, and for her to recover completely after two months, when they steal more of her blood.

As a young woman having periods, low iron may already be an issue unless she eats healthier than many teens or takes vitamins, probably at the urging of a parent. Lots of teens and young adults have low iron levels for years.

Maryn, five-gallon donor

SKara
05-12-2014, 06:44 PM
Thanks for replying!:D I think now my story is going to be far more realistic than before when I had been relying on guesses.

Cathy C
05-12-2014, 07:59 PM
Thanks. Maybe I could use the holes to hint to her that she has some memory gaps, because finally she has to realize the secret happenings somehow and try to find out the person.

If she has recurring memory lapses along with the holes and/or bruising, it would be absolutely plausible for her to wonder if she IS being drugged. I could see her asking a friend or group of friends to keep watch to see if she's sleepwalking or if someone is breaking into her home. It also gives a place for dialogue, so it's not just her musing to herself in the text about the weirdnesses. Secondary characters ROCK as a method to amp up the fear or mystery. :)

SKara
05-12-2014, 09:01 PM
Brilliant idea! Thanks again!

melindamusil
05-12-2014, 09:40 PM
If you want to explain away the bruises:
When I was in college, I lived in an apartment in a really old house (100+ years). That apartment had a lot of hard edges and protruding cabinets and shelves, plus it was pretty cramped and crowded. Now admittedly, I'm not a very coordinated person. I've never bruised easily, but I would regurlarly find bruises without any memory of hurting myself.

EMaree
05-12-2014, 09:50 PM
I hope the bruising won't appear until the third or fourth time?

It really depends on your donor. Maryn's an experienced donor, so if your MC is a good donor candidate I'd use her advice as a basis for your MC.

I bruise almost every time I donate, though, and if a vein collapses then I bruise very badly. But genetics have given me very thin veins and mysterious other factors give me very low iron, so I'm a worst case scenario.

Quite a few nurses have failed to get any tangible amount of blood out of me. (I'M A STOOOOONE!) Last time I tried to donate the nurse said my right arm had no blood and was "full of air", so I'm currently registered as left-arm only donor. :D

SKara
05-12-2014, 11:37 PM
EMaree, if you don't mind, can I ask why you keep donating blood if you already have iron deficiency? Just curious.:)

Maryn
05-12-2014, 11:38 PM
(That post has me laughing.)

I have "bad veins" but when I warn the nurse, they do what they can to get me in one stick. I require extra monitoring to keep the flow going, too, often moving the needle an eensie bit when it's in place.

But most of the people around me at the blood drive donate easily, the physical donation taking 15 minutes or less and completely pain-free other than the single poke. Body builders, whose veins have enlarged to supply blood to larger muscle mass, are apparently extremely fast donors.

Maryn, who lifts a heavy fork on occasion

EMaree
05-13-2014, 10:07 PM
EMaree, if you don't mind, can I ask why you keep donating blood if you already have iron deficiency? Just curious.:)

A very sensible question to ask! We're very short on donors around here, so as long as the nurses are comfortable taking blood from me I'm up for trying. :) I'm not particularly scared of needles or squeamish about blood so I'd feel awful if I didn't attempt to donate.

I warn them in advance that I'm problematic, they run checks on my iron levels, and the nurses and doctors have been very clear that they'd prefer I try rather than give up.

It's a bit of a trial-and-error process, and it took a long time, a few nurses and a variety of donation centres to discover why these issues were happening. I think it was on my fourth donating attempt that a nurse confirmed my right arm was unusable, and on my next visit they're going to check if they can actually get a full pint out of my left. We've also been going through different spots each time (back of both hands, inside of both elbows, with and without blood pressure cuffs etc). There's still hope we'll crack a way to get blood outta me! :D


I have "bad veins" but when I warn the nurse, they do what they can to get me in one stick. I require extra monitoring to keep the flow going, too, often moving the needle an eensie bit when it's in place.

Oh man, moving the needle feels weird! Not sore, just weird.

They kept a blood pressure cuff on at max setting last time I went (it was just a sample to test, not a full donation). I have to admit, that was a bit scary to go through. Again, not sore, but the feeling of slowly losing my arm freaked me out. I'm hoping to avoid that next time...


But most of the people around me at the blood drive donate easily, the physical donation taking 15 minutes or less and completely pain-free other than the single poke. Body builders, whose veins have enlarged to supply blood to larger muscle mass, are apparently extremely fast donors.

I wonder if that'll work for me? *runs down to the gym*

(Okay, replace 'runs to the gym' with 'takes the dog on a slow walk')

pkbax
05-14-2014, 08:02 PM
They'd have to be very skilled at taken blood, possibly with some supernatural aide if that fits your story. Even if the blood is taken from somewhere out of sight (back of thigh, maybe? Are there easy veins there? They'd have to vary up the spot they use as well...) there'd be a risk of vein collapse & bruising which would draw the MC's attention to the spot.




It really depends on your donor. Maryn's an experienced donor, so if your MC is a good donor candidate I'd use her advice as a basis for your MC.


Although the donor's veins and other factors can affect this, it actually depends on the skill of the phlebotomist (a fancy name for the person doing the collection) more than the donor. We have some people who are very skilled and can draw even problematic donors with no bruising.

Regarding the young lady who fainted, thanks Shea for identifying the real possible causes for this. And I hope someone lets the young lady involved know. Some of the causes can easily be managed so it doesn't happen again should she donate in the future.

Back to the original question about frequency - it has been correctly identified as every 8 weeks for whole blood (at least in the US), which is probably what the person getting the blood from her without her remembering would be drawing. It is easier, quicker and takes less equipment. A "double red" takes longer and a special machine (as do plasma and platelets) called an aperesis machine. The frequency is set for the protection of donor and their health. Of course, that presumes your blood stealer gives a rip about that. If the MC is being coerced into doing this, the person doing it probably doesn't care about the regulations.

PK - who actually works in a Blood Bank

Jamesaritchie
05-15-2014, 12:35 AM
Hi,:)

Does anyone know how much blood an average teenager can donate every month, that is, if they actually can donate every month without risking their health. I have to use the information in my young adult book.

Thanks in advance.

Yes, you can give a pint of blood per month, or even more frequently, without any great risk to your health. You can't, however, do this legally. But this doesn't stop some from getting around the legal limit with a good fake ID, and different places to donate.

I've met several people who manage to donate once per month.

shaldna
05-15-2014, 05:50 PM
Hi,:)

Does anyone know how much blood an average teenager can donate every month, that is, if they actually can donate every month without risking their health. I have to use the information in my young adult book.

Thanks in advance.


I used to work for the National Blood Service and in the UK you have to be over 17 and under 66 to donate blood and you can do it every 12 weeks. Although you will routinely only be called every 6 months. That said, the NBS discourage women from donating until after 16 weeks have passed.

However, your weight also matters - you have to be at least 7 stone 12, and within all the correct circumstance - ie. not be pregnant, not have had a tattoo, acupuncture or piercings within the last 12 months etc.

Quentin Nokov
05-16-2014, 01:19 AM
How long after receiving blood can one donate? My mother had a blood transfusion in 2011 (she became mysteriously anemic) And I forgot how long one has to wait before donating again after having been given blood.

Maryn
05-16-2014, 06:09 PM
In the US, if you received a transfusion using blood donated in the US, you have to wait 12 months before you can donate.

If you got a transfusion in the UK or France any time after 1979, you cannot donate ever, because of the risk of spreading mad cow disease.

I don't know about any other places' rules.

Maryn, whose cows are friendly

EMaree
05-16-2014, 07:15 PM
I used to work for the National Blood Service and in the UK you have to be over 17 and under 66 to donate blood and you can do it every 12 weeks. Although you will routinely only be called every 6 months. That said, the NBS discourage women from donating until after 16 weeks have passed.

However, your weight also matters - you have to be at least 7 stone 12, and within all the correct circumstance - ie. not be pregnant, not have had a tattoo, acupuncture or piercings within the last 12 months etc.

Not sure about the NBS, but the 'no tattoo' rule isn't quite right in most of the UK. Blood.co.uk (England) says it has to be 4 months (http://www.blood.co.uk/giving-blood/who-cant-give-blood/) since you had a tattoo, with the NHS (http://www.nhs.uk/Conditions/Blood-donation/Pages/Who-can-use-it.aspx)confirming this, ScotBlood (Scotland) (https://www.scotblood.co.uk/can-i-donate/tattoopiercing.aspx) says 12 months after a tattoo.

I think they might have decreased this time very recently, because I'm *sure* it was six months in England last year.