The fetus may need one or more blood transfusions before birth. A fetus with severe Rh disease who survives the pregnancy may need a blood exchange. This procedure replaces most of the infant's blood with donor blood usually type O, Rh-negative. A history of pregnancy with Rh disease is a sign that you will need special treatment when you are pregnant with an Rh-positive fetus.
What Increases Your Risk Rh sensitization can occur when a person with Rh-negative blood is exposed to Rh-positive blood. Things that increase the risk of blood mixing and sensitization during pregnancy include: Delivery. Abdominal trauma, such as from a car accident. Abdominal surgery, such as a cesarean section.
Placenta abruptio or placenta previa , both of which can cause placental bleeding. External cephalic version for a breech fetus. Obstetric procedures such as amniocentesis , fetal blood sampling, or chorionic villus sampling CVS. Miscarriage spontaneous abortion , ectopic pregnancy , or elective abortion medical or surgical abortion after 8 weeks of fetal age when fetal blood cell production begins. Partial molar pregnancy involving fetal growth beyond 8 weeks.
When should you call your doctor? If you are already Rh-sensitized and are pregnant Your pregnancy will be closely monitored. If you are Rh-negative Call your doctor immediately if you: Think you may have been pregnant and miscarried. Are pregnant and have had an accident that may have injured your abdomen. Who to see A woman who may have problems with Rh incompatibility or sensitization can be treated by: A family medicine doctor , for mild fetal Rh disease.
An obstetrician , for mild to moderate Rh disease. A perinatologist , for moderate to severe fetal Rh disease hydrops. Exams and Tests If you are pregnant, you will have your first prenatal tests during your first trimester. If you are Rh-negative and your partner is Rh-positive, your fetus is likely to be Rh-positive.
If you are Rh-negative All pregnant women have an indirect Coombs test during early pregnancy. At the first prenatal visit, your blood is tested to see if you have been previously sensitized to Rh-positive blood. If you are Rh-negative and test results show that you are not sensitized, a repeat test may be done between 24 and 28 weeks.
If test results at 28 weeks show that you have not been sensitized, no additional tests for Rh-related problems are done until delivery barring complications such as placenta abruptio. You will also have a shot of Rh immune globulin.
This lowers your chances of being sensitized during the last weeks of your pregnancy. If your newborn is found to be Rh-positive, your blood will be screened again at delivery with an indirect Coombs test to see if you have been sensitized during late pregnancy or childbirth.
If you have not been sensitized, you will have another shot of Rh immune globulin. If you are sensitized to the Rh factor If you are already Rh-sensitized or become sensitized while pregnant, close monitoring is important to determine whether your fetus is being harmed. If possible, the father will be tested to see if the fetus could be Rh-positive.
If the father is Rh-negative, the fetus is Rh-negative and is not in danger. If the father is Rh-positive, other tests may be used to learn the fetus's blood type. In some medical centers, the mother's blood can be tested to learn her fetus's blood type. This is a new test that is not widely available. An indirect Coombs test is done periodically during your pregnancy to see if your Rh-positive antibody levels are increasing.
This is the typical course of treatment for most sensitized women during pregnancy. Fetal Doppler ultrasound of blood flow in the brain shows fetal anemia and how bad it is. At a medical center with Doppler experts, this test can give you the same anemia information as amniocentesis, without the risks.
Amniocentesis may be done to check amniotic fluid for signs of fetal problems or to learn the fetus's blood type and Rh factor. Fetal blood sampling cordocentesis may be done to directly assess your fetus's health. This procedure is used on a limited basis, usually for monitoring known sensitization problems as when a mother has had previous fetal deaths, or when other testing has shown signs of fetal distress.
Electronic fetal heart monitoring nonstress test may be done in the third trimester to check your fetus's condition. Unusual fetal heart rhythms detected during a nonstress test may be a sign that the fetus has anemia related to the sensitization. Fetal ultrasound testing can be used as a pregnancy progresses to detect sensitization problems, such as fetal fluid retention a sign of severe Rh disease. Treatment Overview If you are sensitized to the Rh factor If your blood is Rh-negative and you have been sensitized to Rh-positive blood, you now have antibodies to Rh-positive blood.
Treatment options depend on how well or poorly the fetus is doing. If testing shows that your fetus is Rh-positive but is only mildly affected by your Rh factor antibodies, you will be closely watched until your pregnancy reaches term. Your fetus will be delivered early only if his or her condition gets worse.
If testing shows that your fetus is moderately affected by your Rh antibodies, your fetus's condition will be closely watched until his or her lungs are mature enough for a preterm delivery. A cesarean section may be used to deliver the baby quickly or to avoid the difficulty of inducing labor before term.
A moderately affected newborn sometimes needs a blood transfusion immediately after birth. If testing shows that your fetus is severely affected by your Rh factor antibodies, a blood transfusion may be given before birth intrauterine fetal blood transfusion. This can be done through the fetus's abdomen or directly into the fetus's umbilical cord.
A preterm delivery is likely to be needed. Multiple blood transfusions are sometimes needed to keep a fetus healthy until the fetal lungs mature enough to function after birth.
The combination determines your Rh status, as shown in the table below. Being Rh- does not affect your health, but it can complicate a pregnancy. If the baby's blood type matches the mother's both are Rh- , Rh causes no complications. Red blood cells with the Rh factor are foreign to the mother.
The process is called sensitization—the mother is now sensitized to the Rh factor. During the first pregnancy, this usually does not present any danger to the fetus.
Most often, the baby is born before the mother develops enough Rh antibodies to do harm. Although some red blood cells leak across the placenta during pregnancy, the greatest amount is transferred at delivery. In addition, Rh antibodies can develop after a miscarriage , abortion, ectopic pregnancy , or amniocentesis.
Rh sensitization can cause problems for a baby in later pregnancies. This causes hemolytic disease due to Rh incompatibility. It is an anemia that can cause serious complications in the infant, including brain damage and even death. Although Rh disease is rarely seen in the first pregnancy, later pregnancies are at an increasingly greater risk.
Women who are Rh- but unsensitized are given a shot of Rh immune globulin at around 28 weeks of pregnancy. Rh- immune globulin contains antibodies to the Rh factor. Rh-immune globulin's protective effect lasts for about 12 weeks, so the shot will be given again during future pregnancies. An Rh-sensitized pregnancy is a high risk pregnancy. During an Rh-sensitized pregnancy, the mother's blood is tested for Rh antibodies throughout the pregnancy.
If the amount of antibodies is rising to an unsafe level, tests are done to assess the health of the fetus. In some situations, the doctor may advise inducing early labor and giving blood transfusions to the newborn child. In the last two decades, many advances have been made in treating a fetus with severe Rh disease.
Neonatal jaundice and liver diseases. Fanaroff and Martin's Neonatal-Perinatal Medicine. Philadelphia, PA: Elsevier; chap Kliegman RM, St. Blood disorders. In: Kliegman RM, St. Nelson Textbook of Pediatrics. Moise KJ. Red cell alloimmunization. Gabbe's Obstetrics: Normal and Problem Pregnancies. Updated by: Neil K. Editorial team. Rh incompatibility. After birth, the infant may have: Yellowing of the skin and whites of the eyes jaundice Low muscle tone hypotonia and lethargy.
Exams and Tests. If you're Rh negative and your baby is Rh positive, your body might produce proteins called Rh antibodies after exposure to the baby's red blood cells. The antibodies produced aren't a problem during the first pregnancy. The concern is with your next pregnancy.
If your next baby is Rh positive, these Rh antibodies can cross the placenta and damage the baby's red blood cells. This could lead to life-threatening anemia, a condition in which red blood cells are destroyed faster than the baby's body can replace them. Red blood cells are needed to carry oxygen throughout the body.
If you're Rh negative, you might need to have another blood test — an antibody screen — during your first trimester, during week 28 of pregnancy and at delivery.
The antibody screen is used to detect antibodies to Rh positive blood. If you haven't started to produce Rh antibodies, you'll likely need an injection of a blood product called Rh immune globulin. The immune globulin prevents your body from producing Rh antibodies during your pregnancy. If your baby is born Rh negative, no additional treatment is needed.
If your baby is born Rh positive, you'll need another injection shortly after delivery. If you're Rh negative and your baby might be or is Rh positive, your health care provider might recommend an Rh immune globulin injection after situations in which your blood could come into contact with the baby's blood, including:.
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