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Blood Types & Incompatibilities
MAJOR BLOOD TYPES
Blood typing is an important test that should be done prenatally. There are over 100 factors present in the red blood cell, however, there are only a few that can cause sensitization problems in pregnancy and during childbirth. The other factors do not cause any significant problems as they are very weak. The four types of human blood are A, B, AB and O. Each factor refers to a specific antigen (proteins which cause the formation of antibodies).
Type A has A antigens and lacks B factors and therefore recognizes B as a foreign substance.
Type B has B antigens and lacks A factors and therefore recognizes A as a foreign substance.
Type AB has both A and B antigens and has no problem with accepting both of these substances into the body system. It recogizes all bloods as compatible.
Type O lacks both antigens (A and B) and recognizes both of these factors as foreign substances.
When a foreign blood protein is identified, the antigen causes an antibody to be formed in the body system so that the invading substance can be destroyed in the future if the substance is introduced into the body system again. In the case of of these four blood groups, the antibodies are congenitally present in the body system by means of the blood group.
BLOOD GROUP ANTIGEN ON RBC ANTIBODIES IN SERUM O (46%) None Anti - A & B
(Universal Donor)A (41%) A Anti - B B (9%) B Anti - A AB (4%) A & B Neither
(Universal Recipient)
These four blood groups contain those blood proteins that are the most reactive when wrongly combined with each other (such as in a wrongly matched transfusion). This is due to the inherent sensitivity of the blood cells and the immediate antibody reaction that occurs with foreign blood factors.
BLOOD GROUPS & NUTRITIONAL DIFFERENCES
The basic reason is that one's blood type determines compatibility or incompatibility with certain foods. Essentially, incompatibilities agglutinate cells.
Certain foods, and food groups act like poisons to certain blood types. What can be a medicine for one person, can be a poison for another. How is this possible? Because of genetics. You were born with a basic blood type. O, A, B, or AB. You got it from your parents genes. Genes have a way of representing a bit of genetic history.
Type O blood is the oldest blood and shows a connection to the hunter-gatherer cultures. This blood type is strongly aligned with high protein consumption in the form of animal meat and individuals with type O blood generally produce higher stomach acids. This is typically the group that experiences more incidence of gastric ulcer disease than the other groups. Type O's handle animal protein well but grains like whole wheat, and dairy products are not so good. Type O groups comprise about 46% of the American population.
Blood group A was the next to evolve and merged with the development of agricultural practices. Blood group A is primarily associated with vegetarian food sources and individuals in that group secrete smaller amounts of stomach acid. Protein requirements are not any less than a group O person but the source is different. Type A's do poorly with the typical meat and potato fare and are predisposed to heart disease, cancer, and diabetes. Soy proteins, grains, and vegetables are very important for type A's as well as food that is fresh, pure and organic. Group A comprises 42% of the American population.
Then there is type B and AB.
The key to all of this is lectin chemistry. Different blood types are incompatible with the lectins (proteins) of certain food groups. In learning live blood microscopy, the clinician needs to intimately understand the importance of serotyping (blood typing) and the patient's dietary history in relationship to the microscopic findings.
ABO INCOMPATABILITY
ABO problems are relatively common, but less severe than aquired blood incompatabilities. Since the antibodies for another type are inherently present on the red blood cells and do not increase, reactions are usually less severe. The infants at risk are:
- Group A or B infants of Group O mothers (50% of all cases). Mother O, baby A is more common. Mother O, baby B is more severe. Some midwives will take cord blood on all type O mothers due to this frequency.
- Group B or AB infants of Group A mothers.
- Group A or AB infants of Group B mothers.
Theory is that severe cases are usually not seen because they abort spontaneously. Another interesting item about ABO problems is that an Rh- mother with sufficient Anti-A or Anti-B in her system will often destroy any invading fetal blood BEFORE an aquired sensitization can be established. However, this cannot be depended on as a preventative.
Rh FACTORS
Rh (Rhesus) factors are the second most reactive substances to be found in the blood. These are a group of related factors which usually occur together and of which Rho (D) is the most reactive. The Rho
When Rh+ (Rh positive) blood is introduced into the body system of an Rh- (Rh negative) person, the Rh- blood recognizes the Rh factor as a foreign substance and begins to form antibodies in order to destroy the invading cells. Rh+ blood may enter the blood stream of an Rh- person in any of the following ways:
- A wrongly typed blood transfusion.
- A placental leakage due to slight abruptions during the pregnancy of an Rh- pregnant woman carrying an Rh+ baby. This can immunize the Rh- baby against Rh+ blood factors in an Rh+ woman before birth, although this is not common.
- Slight abruptions or invasive medical diagnostic procedures (such as amniocentsis) performed during pregnancy which may allow the mother's and baby's blood to mix and initiate antibody formation with an Rh- mother and an Rh+ baby.
- After the birth of an Rh+ baby when placental detachment takes place and the bloodstream of the mother and baby may mix, the Rh+ blood may enter the maternal bloodstream and initiate antibody formation (whole blood usually does not mix in the normally detached placenta during pregnancy).
The initial introduction of Rh+ blood into the Rh- body system causes no immediate adverse reaction. However, during the days following the blood mixing incident, antibody formation takes place. The anti-Rh antibodies will remain in the system of the Rh- person to destroy any other Rh+ blood with which it comes into contact. With a sensitized pregnant women this means that any future pregnancies with a Rh+ baby may be compromised because the anti-Rh antibodies cross the placenta and may result in blood cell destruction in the Rh+ baby. Sensitization can become progressively worse as more Rh+ babies are carried by an sensitized Rh- pregnant woman (this does not always happen). Any Rh- babies she carries are not at risk.
If both parents are Rh-, they will probably have Rh- babies. However, it is possible for two Rh+ parents to have an Rh- baby if both are carrying a gene for Rh negativity and pass it to their offspring (this happened in my family with my few of my sisters and with my own daughter being Rh- with two Rh+ parents).
Du FACTOR (Duffy factor)
The Du factor is related to the Rh group of blood factors. It is important because in cases where the Rh group is missing (Rh-), the Du factor is sometimes present. In such situations, the Du factor usually compensates for the lack of other Rh factors and causes the blood stream to respond as if it where Rh+. Such cases would be reported as Rh- Du+. These women are RARELY at risk for Rh problems and are most often treated as if Rh+ (except with a transfusion).
KELL FACTOR
About 90% of the population is Kell negative, leaving the other 10% Kell positive. Although the Kell factor is rare, it is strongly antigenic and is significant in a small percentage of pregnancies. Anti-Kell antibodies can be formed in response to a Kell+ transfusion into a Kell- person. This can cause severe hemolytic transfusion reactions. This is the most common way for a Fell sensitization to occur. A Kell+ baby could also sensitize either case, subsequent Kell+ babies would be at risk for hemolytic anemia. It is good to know the father's blood type since one out of 500 people have both genes dominant for the Kell factor, most have a dominant and recessive gene which can result in a 50% chance of contributing a Kell+ gene to the baby. In cases of previous sensitization of a Kell- mother, if the baby's father is Kell+, gene contribution during the type of conception can determine the chances of a Kell+ baby.
OTHER MINOR FACTORS
C and E factors are also minor factors which, together with Kell, contribute to 2% of all neonatal incompatibility problems. If a infant develops early jaundice for no apparent cause, then it is important to obtain detailed blood typing of both parents to determine the reason for jaundice. These factors are routinely not checked during prenatal blood typing studies.
LAB TESTS
The lab should check for the major blood types (A,B,AB,O) and the Rho (D). If the woman is found to be Rh+ or Rh- Du+ no further testing is necessary. If any of the following conditions are present these further tests may be important to perform:
- The mother is Rh- and pregnant for the first time.
- The mother is Rh- with known sensitization from a previous pregnancy or transfusion.
- The mother has obtained anti-Kell antibodies after being sensitized from a previous pregnancy or transfusion and the father is Kell+.
- The mother is Rh- and has not been sensitized by a previous pregnancy.
If the father has been checked to make sure he can only produce Rh- offspring should the mother pass on any further testing. This is especially important in situations where blood products (such as Rhogam) are not used for religious reasons. The genetic testing (zygosity) can help the parents to determine what risks they may be taking and plans can be made for the number of children they may be considering for their family.
INDIRECT COOMBS TEST
This test can screen for minor blood factors and the presence of antibodies in the body system. It is always done on an Rh- mother and some labs may do it with every mother to make sure that there are no antibodies present (such as a A+ mother with an anti-Kell). This test detects the presence of antibodies (anti-Rh and others) only. If the Indirect Coombs comes up positive, another test is necessary to determine the type and level of antibody in the blood.
Rh ANTIBODY TITER
If an Indirect Coombs test comes back positive, this test determines the type and quantity of antibodies in the blood. Since the anti-Rh is the most sensitizing, they are the ones most likely to rise during the pregnancy and cause problems. Depending on the level of other antibodies (anti-Kell), etc.) they could cause hemolytic problems in the baby and need to be monitored. It will need to be repeated several times during pregnancy (32 weeks, 36 weeks, and 38 weeks). A low titer (no higher than 1:16) may not represent a problem for the baby. In any test higher than 1:64 or above, a intrauterine exchange transfusion may be suggested (risks and benefits should be thoroughly research before performing this procedure and discussed completely with the clients). A woman with severe Rh sensitization carrying an Rh+ baby is not a candidate for a home birth. However, it is possible for a mother with a high titer to deliver a perfectly healthy Rh+ baby without the resulting jaundice.
DIRECT COOMBS TEST
This test determines the presence of antibodies on the red blood cells (RBCs). It allows the midwife to know if the baby's blood cells are being destroyed and diffentiates what antibody reaction may be occuring (Rh, Kell, etc.).
BILIRUBIN TESTS
A bilirubin test may be done to determine how much RBC destruction is occuring and how fast it is happening. Serial titers will be done to determine how fast the rate is rising or falling. This determines the relative risk to the baby. Bilirubin is the byproduct of RBC destruction and this test is a measure of the result of the hemolytic process.
KLEIHAUSER-BETKE STAIN
In any case where a possibility of blood mixing is suspected, the Kleihauser-Betke stain should be done. This test calls for maternal blood to be taken in a lavendar top (EDTA) tube. It checks for fetal blood cells in the mother's system and is usually done only when excessive fetal transfusion is suspected to determing if the mother needs more than one injection of Rhogam. One dose of Rhogam covers 15 ml of fetal red blood cells or 30 ml of fetal whole blood.
The Kleihauser-Betke stain could also be used to determine whether fetal transfusion has taken place in any Rh- mother of an Rh+ baby, in order to avoid an unnecessary injection of Rhogam. A small transfusion of fetal cells should be detectable, as this test is very sensitive. However, a slight risk of sensitization is still present.
RHOGAM
When a Rh- mother gives birth to a Rh+ baby, an injection of Rhogam will be recommended. Rhogam is an immume globulin substance derived from human blood serum. It works by entering the maternal bloodstream and tagging any fetal blood which may be present rendering it invisible to the mother's body system until she can eliminate it. The sensitization is avoided. Occasionally two or more injections will be necessary, based on the amount of fetal blood in the mother's system. Rhogam is administered within 72 hours after the birth in the upper, outer quandrant of the mother's buttock area (behind and below the pelvic crest on the outside of the body). Although it is reported as being very effective, Rhogam does not totally eliminate the possibility of problems.
Some things to remember when Rhogam treatment is considered:
- Rhogam is a blood product. For some clients (Jehovah's Witnesses) who use no blood products medically, it is a matter of individual choice whether they accept Rhogam as a blood product or not. The midwife needs to determine how she feels about personal preferences and her midwifery practice under these circumstances and whether there are Jehovah Witness health care practitioners in the region that support this choice.
- Since Rhogam is a blood product, reactions similar to transfusion reactions may occur. Symptoms include:
- Heat at the injection site.
- Constricting pain in the chest or lumbar region.
- Flushing of the face.
- Bleeding from wounds.
Symptoms may be milder than a blood transfusion, but medical help should be sought immediately.
Before Rhogam is administered, the lab must recheck the mother's blood for blood type and factor sensitivity to make sure she is Rh- and that she has remained unsensitized.
- Blood related diseases can be passed to the mother (hepatitis, HIV, etc.). I have not heard of a synthetic form of Rhogam developed yet at this time.
- Rhogam is administered in any of the following situations:
- The transfusion of Rh+ blood into the blood stream of an Rh- person.
- When an unsensitized woman has given birth to an Rh+ baby and has a negative Direct Coombs test.
- When an unsensitized woman has a miscarriage or abortion (sensitization usually doesn't occur before 8 weeks gestation).
- After an Rh- woman undergoes an invasive diagnostic procedure involving potential bleeding (such as amniocentesis).
- Many medical practitioners are recommending Rhogam prophylactically for ALL unsensitized Rh- women. This is very expensive and another example of medical misuse and abuse of a practice that was meant to help a few, but is not required for the entire population.
Approximately 13% of those Rh- mothers who have not received Rhogam after giving birth to a Rh+ baby will become sensitized during their first pregnancy. Rhogam is said to be about 93% effective (which means it is not always effective for preventing sensitization).
Rhogam is an expensive product requiring a prescription. Most midwives do not usually keep a supply on hand since it has a short "shelf-life" and must be discarded when the expiration date is reached. The client can obtain a prescription for the product from her health care provider and have it available for her birth.
With recent developments, there is a standardized type of Rhogam sold as a pharmaceutical product that has fewer problems with blood product reactions occuring and does not need to be crossmatched with the mother's blood type.
CLIENTS & MIDWIVES CHOOSING NOT TO USE RHOGAM
If a woman refused to use Rhogam for religious or other reasons, and the midwife is comfortable working with her and the client's health care provider is supportive, there are things that the midwife and Rh- client can do to reduce the possibility of sensitization during her pregnancy or keeping sensitization to a minimum in a sensitized client. Building a strong placental bed will help to minimize problems.
Some suggestions include the following to be used during pregnancy:
- A good, nutritious diet helps to establish and strengthen the placental bed and minimized the risk of premature separation.
- Citrus fruits and juices three times a day and a bioflavinoid complex tablet (600 mg daily) can help strengthen the placental bed.
- Eliminating fluoridized water and toothpaste (fluoride interferes with the body's ability to form and properly distribute collegen (the principle protein involved in attaching the placenta to the uterus).
- 1 gram of activated charcoal daily.
- 1 teaspoon of magnesium powder in water daily (epsom salts).
- Kelp, sea vegetables or mineral supplements daily.
- Fresh garlic or garlic oil perles (10 perles or 3-6 cloves daily).
- Elder flower tea daily.
These things can be done after the birth to prevent or minimize sensitization from occuring:
- Allow the cord to stop pulsing before cutting. This will allow as much of the blood as possible to drain from the placenta and then creating less of a back-wash on the maternal side. If there is no titer in the mother, it does not increase the likelihood of jaundice in the baby.
- Allow the remaining blood to drain freely into the cord blood tubes and placental pan. Do not clamp the cord until it is completely drained (for the same reason as given above).
- Check the fundus but do not apply massage. Massage can irritate the uterine lining and cause unnecessary bleeding.
- Watch carefully for signs of placental separation and gently assist delivery with cord traction or the mother squatting. Tell the mother to be aware of contractions and push with them. Avoid traumatic placental delivery at all costs!
The following situations will place a woman at higher risk for blood mixing to occur:
- Bleeding during labor. This can be from a slight placental abruption or a marginal placenta previa. Either of these can cause the fetal blood to enter the mother's system.
- Excessive bleeding postpartum associated with partially detached placenta which may be taking some time to deliver.
- Manual or otherwise aggressive placental removal.
- If twins are suspected, clamp immediately to avoid possible twin to twin transfusion.
Eldoncards can be purchased from: Cascade HealthCare Products, Inc., Diagnostic Tests, Blood Typing
Other Purchasing Sources:
Eldoncard.com
Helpful Information
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Information obtained from Understanding Lab Work in the Childbearing Year - A guide for practitioners and consumers of health care in childbirth by Anne Frye. Thankyou Anne!