Importantly, RhD immunoglobulin is currently a finite resource, a blood product that is currently dependent on volunteer plasma donors with high titers of anti-D (who sometimes require boosting with RhD positive blood). As a result in late 2023, the United States Food and Drug Administration (FDA) announced a shortage of RhD immunoglobulin.⁸ The shortage is ongoing as of March 2025. Continued overuse in very low risk situations threatens the ability of RhD-negative pregnant patients without anti-D antibodies to receive the proven benefit of prophylaxis at 28 weeks gestation.

So, who should get RhD immunoglobulin?

It is important to note that recommendations for RhD immunoglobulin in patients experiencing any abortion greater than or equal to 12 weeks of gestation remain unchanged, and these patients should receive 300 μg of RhD immunoglobulin as soon as possible. Similarly, these recommendations only apply to spontaneous or induced abortion, not other potential indications. Lastly, some patients may have strong feelings about RhD prophylaxis. For example, the Society for Maternal Fetal Medicine continue to take a conservative stance, recommending testing and prophylaxis when logistically and financially feasible.⁹ Due to the very low likelihood of benefit in patients with spontaneous abortion at less than 12 weeks of gestation, it is reasonable to engage in shared decision making with your patient.

Dr. Westafer (@Lwestafer) is an assistant professor in the departments of emergency medicine and healthcare delivery and population science at UMass Chan Medical School, Baystate, and co-host of FOAMcast.

References

1. Bowman J. Thirty-five years of Rh prophylaxis. Transfusion. 2003;43(12):1661–6.
2. Practice bulletin no. 181 summary: Prevention of Rh D alloimmunization. Obstet Gynecol. 2017;130(2):481–3.
3. Horvath S, Goyal V, Traxler S, Prager S. Society of Family Planning committee consensus on Rh testing in early pregnancy. Contraception. 2022;114:1–5.
4. [Cited 2025 Mar 19]; Available from: https://iris.who.int/bitstream/handle/10665/349316/9789240039483-eng.pdf
5. ACOG Clinical Practice Update: Rh D immune globulin administration after abortion or pregnancy loss at less than 12 weeks of gestation. Obstet Gynecol. 2024;144(6):e140–3.
6. Visscher RD, Visscher HC. Do Rh-negative women with an early spontaneous abortion need Rh immune prophylaxis? Am J Obstet Gynecol. 1972;113(2):158–65.
7. Horvath S, Huang Z-Y, Koelper NC, et al. Induced abortion and the risk of Rh sensitization. JAMA. 2023;330(12):1167–74.
8. Center for Biologics Evaluation, Research. CBER-regulated products: Current shortages [Internet]. U.S. Food and Drug Administration. 2025 [cited 2025 Mar 18];Available from: https://www.fda.gov/vaccines-blood-biologics/safety-availability-biologics/cber-regulated-products-current-shortages
9. Society for Maternal-Fetal Medicine. Electronic address: pubs@smfm.org, Prabhu M, Louis JM, Kuller JA, SMFM Publications Committee. Society for Maternal-Fetal Medicine Statement: RhD immune globulin after spontaneous or induced abortion at less than 12 weeks of gestation. Am J Obstet Gynecol. 2024;230(5):B2–5.