How can Rh problems affect the fetus during subsequent pregnancies?
Rh sensitization can lead to a wide variety of mild to serious health issues in a fetus or newborn of the next pregnancy. The main concern is a severe type of anemia in the fetus, in which red blood cells are destroyed faster than baby can replace them. Red blood cells carry oxygen to all parts of the body. Without sufficient red blood cells, the fetus will not get enough oxygen, and this can result in hemolytic disease of the fetus and newborn causing jaundice, brain damage, heart failure and death.
How can my fetus’s blood get into my bloodstream?
During healthy pregnancy, a mom and her fetus usually do not share blood, thanks to the placenta that keeps the fetal and maternal blood circulation separate. But sometimes a small amount of blood from the fetus can mix with the mother’s blood. Typically, there is no mixing sufficient enough to risk sensitization unless there is are complications like miscarriage, placental abruption or previa, abdominal trauma, or an invasive medical/surgical procedure like chorionic villus sampling or amniocentesis, abdominal surgery and even ultrasound.
Sensitization is usually associated with a rapid and large volume of fetal-maternal blood mixing. The most common time for Rh-positive fetal red blood cells to enter mother’s bloodstream, is during childbirth, though it can occur at other points during pregnancy - mainly in the third trimester.
Traumatic and difficult births with a high level of invasive procedures increase the likelihood for baby’s blood to mix with mom’s. So can certain routine interventions including use of the synthetic drug Pitocin to induce or augment labor, local or regional anesthesia, forced directed pushing, clamping the umbilical cord too early, pulling on the cord and putting pressure on the fundus to hasten delivery of the placenta.
A gentle birth process with minimal intervention and time allowance for the placenta to separate provides a reduced risk of significant mixing of blood between mother and baby.
While not a guarantee, planning for a natural undisturbed physiologic pregnancy and birth may certainly help prevent the mixing of fetal and maternal blood that leads to sensitization and hemolytic disease.
Can you tell if the baby is Rh-positive?
There is a new noninvasive blood test, which can detect fetal blood type using a blood sample of the pregnant mom. It is said to be highly accurate, almost as reliable as the conventional test, that uses a blood sample of the newborn after birth. It is almost, but not 100% accurate; and it is not available everywhere or covered by all insurances.
I recommend dad getting his blood type and Rh factor tested. If the father is Rh-positive and the mother is Rh-negative, there is about a 75% chance baby is Rh-positive, and providers will probably recommend RhoGAM. But if both parents are Rh-negative, baby will also be Rh-negative; in that case, there is no risk of Rh sensitization, and no need for RhoGAM.
What is RhoGAM?
RhoGAM is a drug made from human blood plasma, that prevents the mother from making antibodies against the positive Rh factor in baby’s blood. It is given via intramuscular injection, to prevent the immune response of sensitization against baby’s Rh positive blood, and subsequent hemolytic disease of the fetus or newborn in future pregnancies.
What are the benefits of RhoGAM?
RhoGAM’s effectiveness has been demonstrated in multiple studies around the globe. According to Dr. Murray Enkin et.al of A Guide To Effective Care in Pregnancy and Childbirth , one of the widely respected and authoritative founders of evidence based care, RhoGAM given after birth reduces the rate of hemolytic disease from 15% down to 1.6%. RhoGAM administration prenatally in the third trimester has been shown in studies to further decrease the incidence to 0.06%.
The administration of RhoGAM medication to Rh-negative mothers is thought to be a major achievement of modern obstetrics by many in the medical profession. Before RhoGam’s introduction into routine practice in the 1970s, hemolytic disease of the newborn was a major cause of serious illness, death and long term disability in babies.
RhoGAM does not typically benefit firstborn babies unless the mom who is Rh negative has previously experienced a reaction to a mismatched blood transfusion, an abortion, miscarriage or ectopic pregnancy untreated with RhoGam.