# Blood Types and RH Factors **URL:** \ **Category:** Factual Questions\ **Created:** [June 8, 2015, 10:48pm UTC](https://boards.straightdope.com/t/blood-types-and-rh-factors/722016 "2015-06-08T22:48:31Z")\ **Posts on this page:** 7\ **Page:** 2
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [June 11, 2015, 9:45pm UTC](https://boards.straightdope.com/t/blood-types-and-rh-factors/722016/21 "2015-06-11T21:45:52Z")
Correction: A+ is high in demand. It’s just that it’s also high in supply. ---
**Author:** ![Cartoonacy](https://avatars.discourse-cdn.com/v4/letter/c/848f3c/32.png) [@Cartoonacy](https://boards.straightdope.com/u/Cartoonacy)\ **Post date:** [June 11, 2015, 11:13pm UTC](https://boards.straightdope.com/t/blood-types-and-rh-factors/722016/22 "2015-06-11T23:13:19Z")
I’ve no doubt that all blood types are high in demand. I just assumed from md2000’s post that O+ and A+ are the lowest. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [June 11, 2015, 11:40pm UTC](https://boards.straightdope.com/t/blood-types-and-rh-factors/722016/23 "2015-06-11T23:40:59Z")
His post said that anything other than A+ or O+ is rare. That implies that A+ and O+ are not rare, which in turn implies that they’re in high demand (since they’re common types for patients needing blood, too). ---
**Author:** ![Cartoonacy](https://avatars.discourse-cdn.com/v4/letter/c/848f3c/32.png) [@Cartoonacy](https://boards.straightdope.com/u/Cartoonacy)\ **Post date:** [June 12, 2015, 8:46pm UTC](https://boards.straightdope.com/t/blood-types-and-rh-factors/722016/24 "2015-06-12T20:46:23Z")
> [@Chronos](#): > > That implies that A+ and O+ are not rare, which in turn implies that they’re in high demand (since they’re common types for patients needing blood, too). How does “not rare” imply “in high demand?” I have no doubt that all blood types are needed, but I’m not following the logic. ---
**Author:** ![tapu](https://avatars.discourse-cdn.com/v4/letter/t/49beb7/32.png) [@tapu](https://boards.straightdope.com/u/tapu)\ **Post date:** [June 12, 2015, 9:10pm UTC](https://boards.straightdope.com/t/blood-types-and-rh-factors/722016/25 "2015-06-12T21:10:50Z")
I’m AB+. Been in the platelet donation program off and on for years. It’s a bit of a pain–at times literally–but they work hard to keep me coming back. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [June 13, 2015, 3:28pm UTC](https://boards.straightdope.com/t/blood-types-and-rh-factors/722016/26 "2015-06-13T15:28:19Z")
The kind of blood that’s needed is the kind that the patient has. If a lot of people in general have A+ blood, then a lot of patients will have A+ blood, because people are just as likely to get into accidents etc. no matter what blood type they have. If a lot of patients have A+ blood, and patients should get their own blood type, then the demand for A+ blood is high. ---
**Author:** ![WhyNot](https://avatars.discourse-cdn.com/v4/letter/w/c77e96/32.png) [@WhyNot](https://boards.straightdope.com/u/WhyNot)\ **Post date:** [June 13, 2015, 3:45pm UTC](https://boards.straightdope.com/t/blood-types-and-rh-factors/722016/27 "2015-06-13T15:45:25Z")
> [@Chronos](#): > > The kind of blood that’s needed is the kind that the patient has. If a lot of people in general have A+ blood, then a lot of patients will have A+ blood, because people are just as likely to get into accidents etc. no matter what blood type they have. If a lot of patients have A+ blood, and patients should get their own blood type, then the demand for A+ blood is high. And that varies a lot around the world. One thing that anyone doing extended international travel should do is confirm the frequency of their blood type in their destination country, and make arrangements with the local hospital or consulate if their blood type is rare there. This is especially important for B types, which have high representation in Central Asia and very little in the US. Even within the US, there are places where A blood (positive or negative) is more prevalent than others, so both the supply and the demand will vary. [Scroll down for a couple of maps.](http://s155239215.onlinehome.us/turkic/63_Blood_Types/Blood_TypesEn.htm) [Previous page](https://boards.straightdope.com/t/blood-types-and-rh-factors/722016.md?page=1)