Mrs Leena had a miscarriage during her 1^st pregnancy. She underwent a D & C procedure and was advised not to conceive for 6 months. During her second pregnancy it was discovered that Leena was A Rh –ve (Rh Negative). Leena had a still born baby who had died of the Haemorrhagic disease. Somehow, during the abortion, attending doctor had not checked her Blood Group.

WHAT IS RH FACTOR & WHY IS IT CALLED SO?

Like major blood groups A, B, AB & O there is another group called the Rh group. This is an antigen found on the surface of the Red Blood Cells. Most people are Rh +ve, i.e. their RBCs have Rh antigen on their surface. Those who do not have this Rh antigen on the surface are called Rh –ve. In 1940, Landsteiner & Alexander S Wiener discovered this antigen on the surface of RBCs. (ABO system of blood group were discovered 1900 by Landsteiner) It is called the Rh antigen as it is found in Rhesus species of monkeys.

WHY IS RH FACTOR SO IMPORTANT?

If Rh +ve RBCs get into the blood of Rh –ve patients, they start producing antibodies against Rh factor. By the time antibodies are formed, blood is so much diluted that no harm occurs. Harmful reactions may occur when this Rh –ve patient is again exposed to Rh +ve blood. Death also may occur.

WHEN MUST ONE BE CAREFUL ABOUT RH FACTOR?

While examining blood for transfusion, it is an international practice to check both ABO & Rh groups. Another field where caution must be exercised is a pregnant woman.

HOW DOES RH AFFECT A PREGNANCY?

Rh factor is inherited. Child of an Rh –ve mother and Rh +ve father may be Rh +ve. During pregnancy, mother’s and child’s blood mixes freely. Some of child’s RBCs enter mother’s blood stream. Mother’s body then build up Anti-Rh. Most of the antibody is not formed until after the baby is born, however, it seldom causes problems with the first child. Once formed these antibodies don’t die. If the mother becomes pregnant with another Rh +ve baby, she now has a readymade supply of Anti-Rh. The flow of large amounts of her Anti Rh into the child’s blood can cause clumping and destruction of child’s RBCs. This condition is called Erythroblatosis Foetalis. This can result in severe anemia, brain damage or even death. Such reaction takes place in about 1 in 20 cases of a Rh –ve mother and Rh +ve father.

SIGNS & SYMPTOMS

Signs in a newborn:

• Paleness.
• Jaundice (yellow skin and eyes) that begins within 24 hours after delivery.
• Unexplained bruising or blood spots under the skin.
• Tissue swelling (edema).
• Breathing difficulty.
• Seizures.
• Lack of normal movement.
• Poor reflex response.

RISK INCREASES WITH

• Each pregnancy after the first involving different blood types.
• Previous blood transfusions. These might have contained unidentified, incompatible blood types.

HOW TO PREVENT

An Rh –ve mother has to be prevented from forming Anti-Rh antibodies and these dreaded complications would not occur.

A simple blood test can tell about a woman’s Blood group and Rh status. Another blood test called an antibody screen can show if an Rh –ve woman has formed antibodies.

• Obtain prenatal care throughout pregnancy. Medical supervision early in pregnancy is essential to determine the risk of Rh incompatibility.
• Special anti-Rh gamma globulin is given to the mother at 28 weeks gestation and within 72 hours after delivery, miscarriage, ectopic pregnancy or abortion. This prevents formation of antibodies that might affect future infants.

DIAGNOSTIC MEASURES

• Previous history and examination by a doctor. Tell your doctor if you have had a miscarriage or abortion earlier.
• Blood tests to: type mother's, father's and infant's blood; measure the mother's Rh-positive antibodies; and detect hemolytic anemia in the infant's blood.
• Amniocentesis.

POSSIBLE COMPLICATION

• Permanent neurological damage, such as cerebral palsy or hearing loss (rare).
• Reaction to Blood-transfusion.

PROBABLE OUTCOME

With prompt recognition of the disorder, damage to the infant can be prevented with exchange transfusions.

TREATMENT

If you have an Rh-negative blood type:

• Tell any doctor who treats you. Make sure this information is in your medical records.

• Rh Immunoglobulin (RhIg) is a blood product that can prevent sensitization of an Rh –ve mother. It suppresses her ability to react to Rh +ve RBCs. RhIg is safe and easily available. With its use sensitization can be prevented almost all the time. RhIg is NOT useful if mother already has antibodies.

IS RHIG SAFE?

Yes RhIg is safe for use in pregnancy. Only known side effects are soreness at the site of the injection.

WHEN IS RHIG USED?

• During pregnancy & after delivery – If the woman with Rh –ve blood has not formed antibodies, she may be given RhIg around 28^th week of pregnancy. This will take care of the small number of patients who develop antibodies in last trimester of pregnancy. Shortly after delivery if child is Rh +ve mother should be injected with RhIg.
• After an abortion as should have been done for Leena.
• After post-partum sterilization as she may decide to have a pregnancy or sterilization may fail.

DO NOT DELAY CALLING YOUR DOCTOR, IF

Your baby has any of the following after returning home:

• Fever.
• Jaundice.
• Poor appetite or poor weight gain.
• Excessive crying that does not stop when the baby is held.