What counseling is recommended for a 29-week pregnant Rh (Rhesus) negative woman, whose babies' father is Rh positive, and who did not receive RhoGAM (Rho(D) immune globulin) in her last pregnancy due to concerns about its effects on her previous baby?

From the Guidelines

This mother should receive RhoGAM (Rh immunoglobulin) at 28 weeks gestation and another dose within 72 hours after delivery if the baby is confirmed Rh positive, despite her concerns about her previous experience. According to the most recent guidelines, all pregnant women should be tested for ABO and Rh (D) blood types and have a serum screen for unusual isoimmune antibodies 1. The American Journal of Obstetrics and Gynecology recommends a 300 mg dose of RhIg when the lower dose is unavailable 1. It's essential to explain that RhoGAM does not affect the fetus directly but prevents the mother from developing antibodies against Rh positive blood. Her belief that RhoGAM made her previous baby sick is a misconception, as the medication doesn't cross the placenta in significant amounts. Without RhoGAM, she risks becoming sensitized to Rh positive blood, which could cause severe hemolytic disease in future pregnancies, potentially leading to fetal anemia, heart failure, or even death. Key points to consider when counseling her include:

• The importance of RhoGAM in preventing sensitization to Rh positive blood
• The risks of not receiving RhoGAM, including severe hemolytic disease in future pregnancies
• The fact that RhoGAM does not affect the fetus directly
• The potential consequences of becoming sensitized to Rh positive blood, including fetal anemia, heart failure, or even death. I would document her concerns, provide educational materials about how RhoGAM works, and possibly arrange a consultation with a maternal-fetal medicine specialist if she remains hesitant.

From the FDA Drug Label

HyperRHO S/D Full Dose is recommended for the prevention of Rh hemolytic disease of the newborn by its administration to the Rho(D) negative mother within 72 hours after birth of an Rho(D) positive infant,(12) providing the following criteria are met: The mother must be Rho(D) negative and must not already be sensitized to the Rho(D) factor. If HyperRHO S/D Full Dose is administered antepartum, it is essential that the mother receive another dose of HyperRHO S/D Full Dose after delivery of an Rho(D) positive infant. If the father can be determined to be Rho(D) negative, HyperRHO S/D Full Dose need not be given HyperRHO S/D Full Dose should be administered within 72 hours to all nonimmunized Rho(D) negative women who have undergone spontaneous or induced abortion, following ruptured tubal pregnancy, amniocentesis or abdominal trauma unless the blood group of the fetus or the father is known to be Rho(D) negative.

The mother is RH negative and the father of the babies is RH positive. Since the mother is 29 weeks pregnant and did not receive Rho(D) immune globulin in her last pregnancy, she should be counseled to receive HyperRHO S/D Full Dose at 28-30 weeks of gestation and again within 72 hours after delivery if the baby is RH positive 2. It is essential to determine if the mother has been sensitized to the Rho(D) factor. If she has been sensitized, HyperRHO S/D Full Dose should not be administered. The mother's concern about the previous pregnancy should be addressed, and she should be informed that the benefits of receiving Rho(D) immune globulin outweigh the risks 2.

• The mother should be monitored for any signs of sensitization to the Rho(D) factor.
• The baby's RH status should be determined after birth to confirm the need for another dose of HyperRHO S/D Full Dose.
• The mother should be informed about the potential risks and benefits of Rho(D) immune globulin administration.

From the Research

Counseling the Mother

• The mother is 29 weeks pregnant, RH negative, and the father of the babies is RH positive.
• She did not receive Rhogam in her last pregnancy due to concerns that it made her baby sick in a previous pregnancy.
• According to the guidelines for preventing Rh alloimmunization 3, anti-D Ig 300 microg should be given routinely to all Rh-negative nonsensitized women at 28 weeks' gestation when fetal blood type is unknown or known to be Rh-positive.
• The study also recommends that all pregnant women (D-negative or D-positive) should be typed and screened for alloantibodies with an indirect antiglobulin test at the first prenatal visit and again at 28 weeks 3.
• Another study suggests that injecting 300 μg anti-D immunoglobulin at 28 and 34 gestational weeks is the most effective measure for preventing maternal antibody sensitization 4.
• It is essential to inform the mother about the importance of Rhogam in preventing Rh alloimmunization and its potential benefits in reducing the risk of hemolytic disease of the fetus and newborn 5, 4, 6.
• The mechanism of tolerance to the Rh D antigen mediated by passive anti-D (Rh D prophylaxis) is not fully understood, but it is hypothesized that down-regulation of antigen-specific B cells through co-ligation of B cell receptors and inhibitory IgG Fc receptors must also occur 7.

Addressing Concerns

• The mother's concern that Rhogam made her baby sick in a previous pregnancy should be addressed by providing information on the safety and efficacy of Rhogam in preventing Rh alloimmunization.
• It is crucial to discuss the potential risks and benefits of Rhogam administration with the mother and provide her with informed consent before administration 3.
• The mother should be informed that the guidelines recommend verbal or written informed consent must be obtained prior to administration of the blood product Rh immune globulin 3.

Management

• The mother should be managed according to the guidelines for preventing Rh alloimmunization, which include administering anti-D Ig 300 microg at 28 weeks' gestation and again at 34 weeks if necessary 3, 4.
• The mother's blood type and antibody screen should be monitored regularly to detect any potential sensitization 3.
• If the mother has any further concerns or questions, she should be referred to a specialist for further counseling and management.