Blood Group Calculator

ABO and Rh Blood group calculator shows what could be the possible blood group or blood type of a child, given the blood groups of biological parents.

A Word of Caution: This calculator should NOT be used for Paternity testing. Sometimes blood grouping inheritance can be flawed due to mutations and give false conclusions and for these reasons we caution all readers to view this calculator and use it only as a predictive tool.Blood Group Discovery: The discovery of A, B, O and combination blood groups ( Blood Group – Animation) by Dr. Karl Landsteiner made it possible to determine a person’s blood group based on a characteristic of specific substances on the surface of red blood cells.

Blood Group Classification

The two most important classifications to describe blood groups in humans are ABO and the Rhesus factor (Rh factor)(1^✔). Knowledge of one's blood group is important for medical reasons. In case of blood transfusion, it is critical that a person gets the same or compatible blood type. When describing the Blood type the Rh +ve or -ve is written as O+ve or AB+ve or O-ve or AB-ve(2^✔).

What is Rh factor?

The Rh blood group system is based on whether or not a person has a protein called the Rh factor on the surface of red blood cells (RBCs). This protein was first found in rhesus monkeys, which is why it's called "Rh." Not all people have the Rh factor on their RBC. Those who have this factor are said to be Rh-positive (Rh+) or D-antigen positive and those who do not, are said to be Rh-negative (Rh¯).

Why is Rh factor important in Pregnancy?

The Rh type is important in Pregnancy because, Rh incompatibility that happens when the mother's blood group is Rh negative and her baby’s blood group in the womb is Rh positive. This mismatch can harm the fetus and cause pregnancy related complications(3^✔). An Rh¯ mother can conceive an Rh+ fetus, if the father is Rh+.During delivery, the fetal RBC may enter the maternal circulation due to leakage and this can result in the immune system of the mother generating antibodies against the fetal Rh factor-bearing RBCs.The firstborn is usually spared since the maternal antibodies are formed only after delivery.If the mother again becomes pregnant with an Rh+ fetus, her antibodies can cross the placenta and attack the fetal RBCs, thereby causing severe hemolytic anemia. The fetal bone marrow reacts to the hemolytic anemia by releasing immature RBCs called erythroblasts into the fetal peripheral circulation, causing erythroblastosis fetalis. In this condition, the baby’s bone marrow releases immature RBCs to compensate for the loss.

Should Blood Group be used for Paternity Testing?

As it was mentioned previously the answer is NO. Both ABO and Rh blood grouping systems for determination of paternity are not conclusive and at best can only be used as predictive tools. Blood grouping are known to be affected by mutations and can give false conclusions.Blood group inheritance is influenced by multiple genetic factors, and there are rare cases where unexpected results can occur due to mutations or uncommon blood types. If your child's blood group does not match with your expectations, please do not suspect your partner. If you require further evidence of Paternity, we suggest you contact an accredited medical diagnostic lab. Genetic testing is generally conclusive for paternity testing. Many labs provide this service in most cities.

Inherited DNA Markers for paternity Testing

Since biblical times, the focus of paternity testing has generally been on alleged fathers who are falsely accused. Major advances for paternity testing occurred between 1940 and 1970 with the discovery of blood group and Rh system and the application of HLA typing to paternity studies. New technology with the use of genetic probes has helped further by identifying inherited DNA markers (4^✔).