Blood Type Compatibility Calculator - Donation, Marriage & Transplant

Check blood type compatibility for donation, marriage, pregnancy & organ transplant. Verify Rh factor risks, hemolytic disease warnings, and Saudi blood bank info

Important Medical Disclaimer

This tool is for educational and informational purposes only and does not replace professional medical advice. Cross-matching tests must always be performed in a laboratory before any blood transfusion or organ transplant. Consult your doctor for accurate recommendations regarding your health condition.

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Blood Type Distribution in Saudi Arabia

O+ 33% Common
33%
A+ 31% Common
31%
B+ 21% Common
21%
AB+ 7% Moderate
7%
O- 4% Rare
4%
A- 2% Rare
2%
B- 1.5% Very Rare
1.5%
AB- 0.5% Very Rare
0.5%

Complete Blood Type Compatibility Matrix

Recipient \ Donor O- O+ A- A+ B- B+ AB- AB+
    Compatible     Incompatible

Blood Banks & Donation Centers in Saudi Arabia

King Faisal Specialist Hospital

Riyadh - Central Blood Bank

011-464-7272

King Salman Center for Kidney Diseases

Riyadh - Blood Bank

011-215-0000

King Abdulaziz Hospital - Jeddah

Jeddah - Blood Donation Center

012-654-1111

King Fahd Hospital - Dammam

Dammam - Blood Bank

013-877-7777

You can also donate blood through mobile donation campaigns organized by the Saudi Ministry of Health and the Saudi Red Crescent in malls and universities.

Understanding Blood Types and the ABO System

The ABO blood group system is the most important system for classifying human blood, discovered by Austrian scientist Karl Landsteiner in 1901, earning him the Nobel Prize in Medicine in 1930 for this groundbreaking discovery. This system relies on the presence or absence of specific antigens on the surface of red blood cells, which are glycoproteins that determine the blood's immune identity. There are two main types of antigens: antigen A and antigen B, and their presence or absence determines four main blood groups.

Blood type A carries antigen A on its red cell surface and produces anti-B antibodies in the plasma. Blood type B carries antigen B and produces anti-A antibodies. Blood type AB carries both antigens and produces no antibodies against either, making it the universal recipient. Blood type O carries no antigens on its cell surface but produces antibodies against both A and B, making its owner a universal donor because the cells will not be rejected by any immune system.

In addition to the ABO system, there is the Rh factor (or Rhesus factor) discovered in 1940. This factor is another protein that may be present (+) or absent (-) on the surface of red blood cells. When combining the ABO system with the Rh factor, we get eight main blood types: A+, A-, B+, B-, AB+, AB-, O+, O-. Each type has unique characteristics regarding compatibility in blood transfusion, marriage, and organ transplantation.

Blood types are inherited genetically from parents according to Mendelian inheritance laws. Each person inherits one gene from each parent, and genes A and B are dominant over gene O. Therefore, a person with blood type A may carry two genes: AA or AO, and a person with type B may carry BB or BO. For blood type O, a person must inherit two OO genes. This explains why two parents with types A and B may have a child with type O. Understanding this inheritance is important in determining possible blood types for children and in forensic medicine.

Blood Donation in the Kingdom of Saudi Arabia

Blood donation in the Kingdom of Saudi Arabia is one of the most important humanitarian acts that saves the lives of thousands of patients annually. Saudi hospitals need more than 900,000 units of blood per year to meet patient needs in accidents, surgical operations, and treatment of chronic diseases such as thalassemia and sickle cell anemia, which are notably prevalent in some regions of the Kingdom, especially the Eastern Province.

The Saudi Ministry of Health has established a comprehensive network of central and branch blood banks across all regions of the Kingdom. These banks collect, test, store blood and its derivatives, and distribute them to hospitals as needed. Each blood bag undergoes rigorous testing including blood type identification, screening for infectious diseases such as Hepatitis B and C, HIV, syphilis, and other tests to ensure the safety of transfused blood. The Kingdom applies the highest quality and safety standards approved by the World Health Organization.

The Kingdom has witnessed notable development in blood donation culture in recent years thanks to continuous awareness campaigns organized by the Ministry of Health, the Saudi Red Crescent, and charitable organizations. Mobile donation campaigns are regularly held in shopping malls, universities, major mosques, and government and private workplaces. The Kingdom has also launched the "Wateen" electronic application to facilitate blood donation, locate the nearest donation center, and find campaign schedules.

Islam emphasizes the preservation of human life and considers saving one life as saving all of humanity. Therefore, senior scholars in the Kingdom have ruled that blood donation is permissible and even recommended when it serves to save a patient's life. Blood donation does not invalidate fasting according to the Council of Senior Scholars' fatwa, which encourages Muslims to donate even during Ramadan. The amount of blood drawn is usually 450 ml, and the body replenishes this volume within 24-48 hours for fluids and 4-8 weeks for red blood cells.

Rh Factor and Its Importance in Pregnancy and Marriage

The Rh factor is one of the most important medical considerations that must be tested before marriage in the Kingdom of Saudi Arabia, and the Saudi Ministry of Health has made it a mandatory part of premarital screening. The main risk occurs when the mother is Rh negative (Rh-) and the father is Rh positive (Rh+), where there is a 50% or greater chance that the fetus will inherit the positive factor from the father, creating an incompatibility between the mother's blood and the fetus's blood.

During the first pregnancy, serious problems usually do not occur because the amount of blood that may transfer from the fetus to the mother through the placenta is limited. However, during delivery, miscarriage, or any bleeding during pregnancy, the mother's body may be exposed to enough positive blood cells to stimulate the production of anti-Rh antibodies. These antibodies remain in the mother's body permanently and pose a risk to any subsequent pregnancy with an Rh-positive fetus.

Hemolytic Disease of the Newborn (HDN) is the main complication of Rh incompatibility. In this disease, the mother's antibodies cross the placenta and attack the fetus's red blood cells, causing them to break down. The severity ranges from mild anemia to severe cases that may cause heart failure or intrauterine death in advanced cases. Post-birth symptoms include severe jaundice, enlarged liver and spleen, and acute anemia.

Fortunately, modern medicine provides an effective and simple solution to this problem through the RhoGAM injection (anti-D immunoglobulin). This injection is given to Rh-negative mothers at week 28 of pregnancy and within 72 hours after delivery if the newborn is Rh-positive. The injection works by preventing the mother's body from producing antibodies, protecting both the current and future pregnancies. The success rate of this preventive treatment exceeds 99%, and all Saudi hospitals provide it as part of the prenatal care program.

Blood Types, Organ Transplantation, and General Health

Blood types play a pivotal role in the success of organ transplant operations and are among the first tests performed when evaluating compatibility between donor and recipient. Organ transplant compatibility primarily depends on the ABO system, where the donor's blood type must be compatible with the recipient's. The general rule is similar to blood transfusion rules: type O can donate to all types, and type AB can receive from all types. However, in organ transplantation, exact blood type matching is preferred to minimize rejection risks.

In addition to blood type compatibility, tissue compatibility must be tested through the Human Leukocyte Antigen (HLA) system. This system is more complex than the ABO system and involves dozens of genes responsible for immune recognition. The greater the HLA match between donor and recipient, the higher the chance of successful transplantation. In Saudi Arabia, the Saudi Center for Organ Transplantation (SCOT) coordinates donation and transplant operations across the Kingdom and manages waiting lists.

Recent scientific studies have revealed fascinating associations between blood types and certain health conditions. For example, some research suggests that people with blood type O may have higher resistance to certain types of malaria, while those with type A may be 20% more susceptible to stomach cancer. Some studies have also found that type O is associated with a slightly lower risk of cardiovascular disease compared to other types.

It is important to emphasize that these are statistical associations and do not mean inevitable disease based on blood type. General health is affected by many factors, most importantly lifestyle, nutrition, physical activity, and other genetic factors. What every person should do is know their blood type and record it on their national ID card or carry it in their wallet, as it is vital information that could save their life in emergencies. Regular blood donation is also recommended as it not only saves others' lives but also improves the donor's own health.

Frequently Asked Questions About Blood Type Compatibility

The most common blood type in Saudi Arabia is O+ (positive) at approximately 33% of the population, followed by A+ at 31%, then B+ at 21%. Negative blood types are less common, with O- at only 4%, A- at 2%, B- at 1.5%, and the rare AB- at only 0.5%. This distribution makes negative blood types particularly important for blood banks.

The Rh factor is a protein found on the surface of red blood cells. If present, the blood type is positive (+); if absent, it is negative (-). Its importance in marriage and pregnancy arises when the mother is Rh- and the father is Rh+, as the fetus may inherit the positive Rh factor from the father. In this case, the mother's body may produce antibodies that attack the fetus's blood, causing Hemolytic Disease of the Newborn (HDN). This can be prevented with a RhoGAM injection during pregnancy and after delivery.

The universal donor is a person with O- (negative) blood type, as they can donate blood to all other blood types because their red blood cells carry no A, B, or Rh antigens. The universal recipient is a person with AB+ (positive) blood type, as they can receive blood from all types because their blood carries all antigens and will not reject any type. However, in medical practice, it is always preferred to transfuse blood of the same type when possible to minimize complications.

Any healthy person aged 18-65 years weighing 50 kg or more can donate blood in Saudi Arabia. Blood pressure and hemoglobin levels must be within normal range. Donation is not allowed for those who had surgery within the last 6 months, received a tattoo within a year, or have certain chronic diseases. Men can donate every 56 days (8 weeks) and women every 84 days (12 weeks). Blood banks at hospitals like King Faisal Specialist Hospital and various donation centers across the Kingdom offer free donation services.

ABO blood type compatibility is essential for successful organ transplantation. The donor's blood type must be compatible with the recipient's according to the same blood transfusion rules. Type O can donate to any type, and type AB can receive from any type. In addition to blood compatibility, tissue compatibility (HLA) must be tested to reduce the likelihood of organ rejection. The Rh factor is less important in organ transplantation compared to blood transfusion, but matching is preferred when possible.

Incompatible blood transfusion can cause acute hemolytic transfusion reaction, a serious condition that occurs when the recipient's immune system attacks the transfused blood cells. Symptoms include: fever and chills, back and chest pain, low blood pressure, nausea, and can lead to acute kidney failure. This is why hospitals perform cross-matching tests before any blood transfusion to ensure complete compatibility. Saudi blood banks follow strict protocols including two independent checks to verify blood type.