MicRhoGAM Shortage: What Providers and Prescribers Need to Know in 2026

The Rho(D) immune globulin (RhIg) shortage that began in December 2023 has significantly impacted the availability of MicRhoGAM Ultra-Filtered PLUS (50 mcg/250 IU, Kedrion Biopharma) in retail pharmacy settings. While production improvements have eased the acute phase of the crisis, OB/GYN providers, emergency medicine physicians, and women's health practitioners continue to navigate inconsistent supply in 2026. This guide summarizes the clinical and operational guidance your practice needs to manage the shortage effectively.

Clinical Background: Why MicRhoGAM Matters

MicRhoGAM (Rho(D) immune globulin human, mini-dose) is indicated for Rh(D)-negative, unsensitized patients following:

Spontaneous or induced abortion at or before 12 weeks of gestation

Ectopic pregnancy at or before 12 weeks of gestation

Threatened abortion at or before 12 weeks of gestation

Transfusion of less than 2.5 mL of Rh-positive red blood cells

The single dose of MicRhoGAM (50 mcg/250 IU) suppresses immune response to 2.5 mL or less of Rh-positive red blood cells. Clinical studies demonstrated that administration within three hours following first-trimester pregnancy termination was 100% effective in preventing Rh immunization. Administration must occur within 72 hours of the at-risk event.

What Caused the Shortage

Per ASHP Drug Shortage Bulletins and FDA announcements, the shortage stems from two primary causes: (1) constraints in the anti-D plasma market — a highly specialized raw material that requires donors with anti-D antibodies — and (2) manufacturing deviations and plant maintenance at Kedrion Biopharma, the sole U.S. manufacturer of MicRhoGAM. Although the WinRho SDF shortage (Kamada) was resolved in August 2024, the Kedrion MicRhoGAM/RhoGAM shortage persisted into 2025–2026 with uneven recovery at the retail pharmacy level.

Approved Alternatives: What You Can Prescribe

There are currently four FDA-licensed sources of Rho(D) immune globulin in the United States (ACOG Practice Advisory, July 2024, reaffirmed March 2025):

HyperRHO S/D Mini-Dose (Grifols): 50 mcg (250 IU) IM. Direct mini-dose equivalent for first-trimester indications. Preferred substitute when mini-dose is required.

RhoGAM Ultra-Filtered PLUS (Kedrion): 300 mcg (1500 IU) IM. Full-dose; per MicRhoGAM prescribing information, may be used if mini-dose is unavailable. Standard for ≥13 weeks gestation.

Rhophylac (CSL Behring AG): 300 mcg (1500 IU) IM or IV. Option for obstetric complications at any gestational age; IV route useful in certain settings.

WinRho SDF (Kamada Ltd.): Multiple strengths IM or IV. Shortage resolved August 2024. IV formulation also used for ITP in non-splenectomized Rh(D)-positive patients.

Write brand-flexible prescriptions when possible (e.g., "Rho(D) immune globulin mini-dose 250 IU IM x1, may substitute HyperRHO S/D Mini-Dose or equivalent") to maximize what's accessible for your patients at their pharmacy.

ACOG Conservation Strategies for Shortage Settings

When supply constraints persist at your institution, the following ACOG-recommended conservation strategies can help prioritize doses for highest-need patients:

Confirm neonatal Rh(D) status from umbilical cord blood before administering routine postpartum RhIg. Only Rh(D)-negative neonates require maternal RhIg be withheld; Rh(D)-positive or unclear status warrants standard prophylaxis.

Consider NIPT for fetal Rh(D) typing in ongoing pregnancies. Cell-free DNA fetal RHD genotyping (e.g., BillionToOne UNITY Fetal Antigen NIPT) can identify Rh(D)-negative fetuses — approximately 40% of RhD-negative pregnant patients — who do not need RhIg at the 28-week visit, conserving limited supply.

Consider paternal Rh testing when paternity is certain. An Rh-negative father cannot father an Rh-positive child, eliminating the need for maternal prophylaxis.

Maintain close inventory monitoring. Track RhIg stores, usage rate, and projected need to identify shortage risk early.

Contact multiple manufacturers and GPO distributors to identify available products across different brand sources.

Communicating With Patients About the Shortage

Patients who have been prescribed MicRhoGAM may be distressed when they find it unavailable — particularly following a pregnancy loss. Reassure patients that:

Equivalent alternatives exist and are clinically interchangeable

The 72-hour window provides time to locate stock, but searching should begin immediately

You can administer the injection in-office if your clinic has supply, saving them from the retail pharmacy search entirely

You can direct patients to use medfinder for providers as a pharmacy locating tool to reduce the burden on your staff. For more guidance on helping patients navigate the shortage, see our provider's guide to helping patients find MicRhoGAM in stock.