Many doctors are following the updated guidelines about the RhRh factor A protein or antigen found on red blood cells. When an Rh-negative mother carries an Rh-positive fetus, her immune system may make antibodies that attack the fetus' red blood cells. immunoglobulinIntravenous immunoglobulin A therapy made from donated antibodies that may help reduce the mother’s immune response and protect the fetus. (RhIgRho(D) immune globulin A preventive treatment that helps prevent Rh-negative mothers from developing antibodies that may harm the fetus.) shot in pregnancy, according to a recent study published in the journal Pregnancy.
Some people have a blood type called Rh-negativeRh-Negative A blood type trait that means your red blood cells lack the Rh(D) antigen.. If an Rh-negative woman is pregnant and their blood mixes with the baby’s Rh-positiveRh-Positive A blood type trait that means your red blood cells have the Rh(D) antigen. blood, their body can start making proteins called antibodiesAntibody A protein made by the immune system that recognizes and attacks foreign substances, such as bacteria, or in HDFN, fetal red blood cells carrying incompatible antigens.. This usually isn’t a problem for that pregnancy.
But in a later pregnancy, those antibodies can cross over and attack the baby’s blood–a condition known as hemolytic disease of the fetus and newborn (HDFN).Doctors can stop this from happening with a shot called RhIg.
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For a long time in the U.S., doctors also gave this shot very early in pregnancy. But newer research found that early in pregnancy, only a tiny amount of the baby’s blood mixes with the parent’s—too little to cause the problem. So in 2022, a group called the Society of Family Planning said doctors can skip the testing and the shot before 12 weeks.
To find out if doctors are following the new guidelines, researchers emailed a survey to 575 specialist doctors across the U.S. About 42% (241 doctors) answered. They found that most doctors have stopped the early testing and shots. About 74% wait until 12 weeks to give the shot.
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But change is not happening the same way everywhere. Doctors in the Midwest and West were much more likely to follow the new rule than doctors in the Northeast. Doctors at Planned Parenthood and independent clinics were more likely to follow it than doctors at big teaching hospitals.
The study also found that “patients rarely or never disagreed with the new guidelines, suggesting that patients may be more open to change than clinicians think,” the study authors said.
