The human body is a miracle. No scientist has been able to describe all of it, even though we have been advancing day by day with new aspects of science. There are millions and trillions of wonderful things, happening inside the body and they keep on changing as we grow older-depending on what milestones in life we pass and what requirements in life we are supposed to fulfill.
Pregnancy is another beautiful process which takes place in the body of a woman and the route followed as it goes on and changes happening inside are unbelievable at times. Not only lay people, but even health care professionals and scientists tend to be surprised by certain phenomenon related to pregnancy and birth and it is just amazing to see how each and everything has been maintained perfectly to carry out reproduction to create off-spring, thus ensuring the persistence of species.
Today in Health Capsule, we are discussing on one of those important topics related to pregnancy-Rh Isoimmunization and and we have obtained the expert advice of Dr. Suranga Hettipathirana, Consultant Gyaenocologist and Obstetrician. Blood covers about 7-8% of the weight of human body and it carries out various vital functions such as transporting oxygen and nutrients to our cells while clearing out waste products like carbon dioxide, ammonia etc., maintaining an effective immune system and a relatively constant body temperature. Blood is a highly specialized tissue, existing in the form of a fluid, composed of more than 4,000 different kinds of components and four of the most important ones include red blood cells, white blood cells, platelets and plasma.
According to Dr. Hettipathirana, all cells- including the ones in blood have a mixture of factors known as antigens on their surfaces which are inherited. Antigens ensure and enable our immune system to identify body’s own cells from non-native or external invaders. When these foreign factors are recognised and differentiated from body’s own cells, they are destroyed by antibodies-the opponent factors which are also produced by the body’s immune system. Antigens are found on the surface of red blood cells where antibodies are found in plasma. All humans produce these blood components where there are no populational or regional differences yet their blood groups can be different depending on the hereditary presence or absence of the antigens A and B on the surfaces of RBCs.
ABO blood types
People with the antigen A on the surface of their RBCs have Blood group A and those with antigen B fall into blood group B. Individuals with AB blood group have both A and B antigens whereas people with type O blood have no antigens present. The antibody which acts against antigen A is called anti-A and is found in the plasma of people who do not carry antigen A on their own RBCs which include people with type O or type B blood. The antibody which acts against antigen B is called anti-B and found in those who do not carry antigen B in their RBCs which include people with type O or type A blood.
Rhesus factor is a protein found in red blood cells. Not all of us carry this factor and people who do are referred to as Rhesus positive and those who do not are referred to as Rhesus negative.
Example: A person with only antigen A and Rhesus factor will fall into blood group A POSITIVE.
Blood grouping can create trouble during pregnancy“When an Rh-negative mother is exposed to Rh-positive Red blood cells, there is a chance for her to produce antibodies inside her body and this is what we call Rh isoimmunization. In fact, when an Rh negative mother gives birth to an Rh positive baby and blood mixes between them by any chance, mother’s body will rapidly start producing antibodies (soldiers in our blood) against baby’s Rh antigens and red blood cells which carry them. Although this will not create any problem
to the mother, baby has a chance to face various unfavourable consequences which can even end up in death.That is why this topic is important to be addressed and created awareness on” highlights Dr. Suranga.
Rh Isomimmunization
A baby’s Rh status is determined by the blood groups of mother and father. If the mother is Rh negative and the father is Rh positive, their baby has at least a 50% chance of being Rh positive. The good news is, this Rh isoimmunization will only take place if the baby’s Rh-positive blood enters the maternal blood circulation and gets exposed to maternal antibodies. Fortunately, the nature has created this phenomenon of pregnancy-- danger-free as much as possible where in most pregnancies, mother’s and baby’s blood would not mix. However, this could take place during,
- Miscarriage
- Induced abortion
- Traumatic deliveries include caesarean section
- Ectopic pregnancy
- Trauma during pregnancy
- Amniocentesis or other invasive testing procedures related to pregnancy which are not very common
- Manual removal of the placenta
- Still Births and intra uterine deaths
First exposure of baby’s blood to mother’s blood (which is called Sensitization) won’t create problems because the initial response would be very slow and antibodies won’t be able to cross the placenta but the re-exposure, causing destruction of baby’s red blood cells can be really quick and lead to so much of trouble.
Consequences can be fatal
- During re-exposure, sensitized Rh negative mother will produce IgG anti-D (antibody) which crosses the placenta and attacks D-positive fetal red cells which are then destroyed in the fetal spleen.
- Result in red cell destruction, liver and spleen enlargement and many more complications in the fetus ultimately ending up with fetal heart and liver failure.
Tackling the problem isn’t difficult at all with the right medical care. With the advances in diagnostic and therapeutic interventions you can definitely get yourself safeguarded from sensitization by following right medical advice.The real problem lies only if you are Rh negative and your husband is Rh positive.During the first doctor visit, make sure to get your blood group checked.If its negative they will do some other tests to see if you have already been exposed to Rh positive blood or not and the treatment will be based accordingly. Anti D immunoglobulin is given following any event with the potential of mixing of maternal and fetal blood. Soon after the delivery, make sure to get your baby’s blood group checked and if its positive another dose of anti D immunoglobulin will have to be taken.
Although the Government sector provides these injections only at potentially sensitising events and delivery, you can get preventive doses from the private sector at 28 and 34 weeks of pregnancy.
While we, the health care professionals will look into taking care of you based on your situation, it is your responsibility to be aware that conditions like this take place in order to support at your best to carry out satisfactory preventive measures and early interventions” underscored Dr. Hettipathirana.
