Not all blood groups run short for the same reason. Some are rare in people. Others are rare on shelves. Understanding the maths takes two minutes and explains every “urgent need” post you have ever seen. ## The Indian population, roughly | Group | Share of people | Shelf risk | |---|---|---| | B+ | ~32,38% | Low, many donors, many patients | | O+ | ~28,32% | High demand, most-used group in emergencies | | A+ | ~20,24% | Moderate | | AB+ | ~7,9% | Low, AB plasma helps everyone | | O− | ~1.5,2% | Highest risk, universal donor, very few carriers | | B− / A− | ~1,2% each | High, rare and patient-specific | | AB− | under 1% | Rarest, AB− patients can only receive AB− red cells | ## Why O− and AB− dominate every “urgent” post O− red cells can be given to almost any patient, that makes O− the emergency-default group when there is no time to crossmatch (accidents, surgeries). But only about 2 in 100 Indians are O−. A small club with a big job. AB− patients sit at the other end: fewer than 1 in 100 people, and they can receive red cells only from AB− and O− donors. When an AB− patient bleeds, the whole state’s banks can be short. ## What this means for you - O−, AB−, B−, A− donors: your rarity is the reason to register. Centres keep a wish-list of rare-group donors and call directly.
- O+ and B+ donors: you are the volume that keeps routine surgery and thalassaemia care running. Shortages in common groups are quieter but constant.
- AB donors (any sign): your plasma is universal, platelet and plasma donation is where you over-deliver. ## The register smooths all of it Shortages are unpredictable; donors are not, once they are on a register. One form and every compatible emergency near you finds you, and blood has no religion, caste or background. Related: rare blood groups · compatibility checker · blood groups explained