Dedicated to Providing Trusted Protection

ACOG antenatal dosing guidelines are based on clinical trials1,2:

  • 300 μg dose of anti-D at 28 weeks gestation was studied in clinical trials3,4
  • This specific dose was expected to ensure 20-30 μg residual anti-D remained in maternal circulation at delivery3
  • When calculating the 300 μg dose, a mean elimination anti-D half-life of ~28 days was assumed4

RhoGAM's half-life aligns with ACOG Guidelines5

Not All Pregnancies Are Alike

Many factors are beyond your control:

  • The timing and amount of fetal-maternal hemorrhage (FMH) is unpredictable and can present without clinical suspicion6,7
  • There is natural, individual variability in the anti-D half-life8
  • The concentration of anti-D circulating in the maternal bloodstream late in the third trimester varies for each pregnancy8
  • The longer the half-life, the greater the residual level in circulation over time9 


1. ACOG practice bulletin. Prevention of RhD alloimmunization. Number 181, August 2017. Obstet Gynecol. 2017;130:e57-e70.3.
2. McMaster conference on prevention of Rh immunization. Hamilton, Ontario, Canada. 28-30 September, 1977. Vox Sang. 1979;36:50-644.
3. Bowman JM, Chown B, Lewis M, Pollock JM. Rh isoimmunization during pregnancy: antenatal prophylaxis. Can Med Assoc J. 1978;118:623-27.
4. Bowman JM, Pollock JM. Antenatal prophylaxis of Rh isoimmunization: 28-weeks’ gestation service program. Can Med Assoc J. 1978;118:627-30.
5. RhoGAM Ultra-Filtered PLUS Prescribing Information, 2015. Kedrion Biopharma Inc.
6. Sebring ES, Polesky HF. Fetomaternal hemorrhage: incidence, risk factors, time of occurrence, and clinical effects. Transfusion. 1990;30:344-357.
7. Pourbabak S, Rund CR, Crookston KP. Three cases of massive fetomaternal hemorrhage presenting without clinical suspicion. Arch Pathol Lab Med. 2004;128:463-65.
8. Bowman JM, Pollock JM. Failures of intravenous Rh immune globulin prophylaxis: an analysis of the reasons for such failures. Trans Med Rev. 1987;1:101-12.
9. Pelican EW. Half-life. In: Glossary of terms and symbols used in pharmacology. Boston, MA: Boston University School of Medicine. Boston University website. Accessed April 13, 2018. 


Important Safety Information

RhoGAM® Ultra-Filtered PLUS [Rho(D) Immune Globulin (Human)] (300 μg) and MICRhoGAM® Ultra-Filtered PLUS [Rho(D) Immune Globulin (Human)] (50 μg) are indicated for the prevention of Rh immunization, including during and after pregnancy and other obstetrical conditions or incompatible transfusion of Rh-positive blood.

RhoGAM® and MICRhoGAM® are made from human plasma. Since all plasma-derived products are made from human blood, they may carry a risk of transmitting infectious agents, e.g., viruses, and theoretically the Creutzfeldt-Jakob disease (CJD) agent.

RhoGAM® and MICRhoGAM® are intended for maternal administration. Do not inject the newborn infant. Local adverse reactions may include redness, swelling, and mild pain at the site of injection and a small number of patients have noted a slight elevation in temperature. Patients should be observed for at least 20 minutes after administration.

RhoGAM® and MICRhoGAM® contain a small quantity of IgA and physicians must weigh the benefit against the potential risks of hypersensitivity reactions. Hypersensitivity reactions include hives, generalized urticaria, tightness of the chest, wheezing, hypotension and anaphylaxis. Patients who receive RhoGAM® and MICRhoGAM® for Rh-incompatible transfusion should be monitored by clinical and laboratory means due to the risk of a hemolytic reaction.

You are encouraged to report adverse events of prescription drugs to the FDA.
Visit or call 1-800-FDA-1088.

Click here for the RhoGAM Full Prescribing Information

This site is intended for residents of the US only.


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