Rh-ve pregnancy is a condition that occurs when the mother’s blood group is Rh-ve and the baby’s blood group is Rh+ve, inherited from the father.
The baby’s blood enters the mother’s blood circulation sometime during the pregnancy and/or labor and childbirth and sensitizes her blood cells.
The mother's blood cells recognizes the foetal cells as foreign and produces Anti-Rh factors to destroy the cells.
The anti-Rh factors have no effect on the mother's cells, but can destroy the fetal red blood cells whenever they come in contact.
These Anti-Rh factors enter the fetal circulation with the mother's blood, either in the same pregnancy or more commonly in a subsequent pregnancy and destroys the fetal red blood cells causing anemia and jaundice in the baby.
Signs and Symptoms of Rh-ve Pregnancy
Since it is the baby who is affected, there are no significant signs and symptoms in the mother.
Management / Treatment of Rh-ve Pregnancy
During pregnancy :
- A thorough history of previous childbirths, any family history of birth of jaundiced babies, or of stillbirths should be taken, since the first baby is usually normal but successive babies are affected.
- Routine blood tests for investigation of the blood group. If the patient is Rh-ve, then the husband’s blood group is checked. If both are Rh-ve, then the baby ia also Rh-ve and there is no fear of the baby being affected.
- Indirect Coomb’s test to detect Rh antibodies in the maternal blood is done at 20 weeks, 32 weeks and 36 weeks of pregnancy.
- If Coomb’s test is positive, then, Anti-Rh D immunoglobin is injected.(Ideally Anti- Rh D immunoglobin should be injected within 72 hours of every delivery and after every abortion).
During Labor:
- Labor is induced at 37 weeks if cervix is inducible.
- Cesarian Section may be needed if the fetus is at risk or if normal labor is not possible.
- The Pediatrician must be informed about the condition of the baby and all preparations must be made for her immediate treatment, if necessary.
Complications in the fetus of an Rh-ve Pregnancy:
Hydrops Fetalis : This is the most severe complication of Rh-ve pregnancy, where the baby suffers from widespread tissue damage. There is edema, enlarged liver and spleen and the baby may die in the uterus.
Icterus Gravis Neonatorum : This is the commonest type of complication, where the baby is not born jaundiced but develops jaundice within a few hours of childbirth. Exchange transfusion of the baby’s blood should be done as early as possible
Kernicterus : The high amount of bilirubin produced during the destruction of the fetal red blood cells may destroy the basal ganglia and the medulla of the baby's brain. The baby may develop convulsions, and be paralysed for life, if she survives.
Hemolytic Anaemia : The baby has anemia at birth due to destruction of RBC’s. Blood Transfusion is necessary.