Screening/Diagnosis:             

 

Rho (D) isoimmunization continues to be a significant perinatal problem.  It results when a Rho (D) negative woman carries a Rho (D) positive fetus.  During pregnancy and delivery, fetal blood cells may entert the mother’s blood causing the mother to become sensitized.  This can lead to fetal hemolysis and removal of red blood cells from the fetal circulation.  All pregnant women should be screened for blood and Rh type and irregular antibodies early in pregnancy, preferably on the initial visit.

 

Rh and antibodies screen - Depending on initial screen

 

A.       Rh Positive - Antibody screen negative

 

B.       Rh Positive - Antibody screen positive

 

C.       Rh negative - Antibody screen negative

 

D.              Rh negative - Antibody screen positive.   

 

 

A.       Rh Positive - Antibody screen negative, no further testing is indicated.

 

B.       Rh Positive - Antibody screen positive, order antibody identification and titer from the Blood Bank and show results to physician or call Duke for further instructions (See E below).

 

C.       RH Negative - Antibody negative, make a note in the chart and recheck at 26-28 weeks. Rh(D) immunoglobulin may be administered after the type and screen is drawn.  It is not necessary to wait for the results, though. It is crucial that the results are checked.  Repeat Rh(D) immunoglobulin has been recommended in 12 weeks, if the patient has not delivered.  

 

Note:  Rh(D) immunoglobulin (RhIg) is also indicated at the time of amniocentesis, miscarriage, abortion and bleeding during pregnancy.

  

The shelf life, cost and method of packaging (may be single dose vial) varies with each drug company.  Patients needing RhIg may receive it at the local health department or hospital. It is not necessary to refer these patients to Duke.   A subsequent positive antibody screen during pregnancy may be explained by the previous administration of RhIg.

 

 

 

 

 

D.       Rh negative - Antibody screen positive:  Obtain antibody identification and titer. If she has Rh antibodies, she should be referred to High Risk Clinic.  If the antibody is not against the Rh (D) antigen, show the results to a physician or call Duke for instructions.  The father of the baby may need to have his antigen status assessed.

E.       Irregular antibodies:  

 

If found at the initial screen, the patient should be evaluated at Duke, unless the antibodies are anti-Lewis or anti-I, which are of no consequence to the fetus. 

 

F.       Other clinical considerations (based on US Preventative Services Task Force recommendations):

·       Administration of a full (300 micrograms) dose of Rh(D) immunoglobulin is recommended for all unsensitized Rh(D)-negative women after repeated antibody testing at 24 to 28 weeks' gestation.

·       Unless the biological father is known to be Rh(D)-negative, a full dose of Rh(D) immunoglobulin is recommended for all unsensitized Rh(D)-negative women after chorionic villus samling, amniocentesis, after induced or spontaneous abortion, ectopic pregnancy and after bleeding during the first trimester.  Bleeding during the second or third trimester, abdominal trauma or fetal death should be evaluated for a fetal-maternal bleeding requiring more than a single dose.

Note:  The Rh negative patient should be informed that Rh(D) immunoglobulin contains plasma, which is a blood product, but Rh(D) immunoglobulin has not been associated with HIV or hepatitis infection in the past.      

 

Prepared in conjunction with the

Division of Maternal-Fetal Medicine

Duke University Medical Center

 

                                                                                                                                    Director 

                                                                      8/7/2008                                       Date 

 

                                                                

 

 

 

 

 

1.      Prevention of Rh D Alloimmunization.  ACOG Practice Bulletin No. 4, May, 1999.

 

 

 

The Clinical Care Guidelines Development Committee of the Perinatal Improvement Board of Duke University Health System has developed a series of multi-disciplinary protocols to offer guidance to health care providers who are caring for pregnant women with high risk conditions.

 

These protocols are designed to assist health care providers in the management of a variety of problems that occur in pregnancy and the time of delivery. They should not be interpreted as standard of care, but instead represent only general guidelines for the care of pregnant women with high risk conditions.  We recognize that services offered by individual providers depend not only on their training, experience and institutional resources, but on the medical facts and circumstances of the specific care situation.

The protocols remain the intellectual property of the Duke University Health System.  They cannot be reproduced in whole or part without the expressed permission of the Health System.

 

These protocols are reviewed by the Department of Obstetrics and Gynecology Division of Maternal-Fetal Medicine, the Department of Pediatrics Division of Neonatology and the Department of Anesthesiology Division of Women’s Anesthesia.  Please contact Andra H. James (andra.james@duke.edu), Chair, Clinical Care Guidelines Development Committee of the Perinatal Improvement Board with ideas for additional protocols.