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APGAR Score Assisted Delivery (FIGO)BPP (Manning Score)Bishop Score CARPREG II Cardiac Risk Cervical Cancer Staging Contraceptive Pearl Index Doppler Matrix (UA/MCA)EFW (Hadlock)Endometrial Staging Endometrial Thickness FGR Criteria (Consensus)FSFI (Sexual Function)Ferriman-Gallwey Score Fetal Anemia (MCA PSV)GDM Diagnostic Criteria GPA History Indicator Gail Model Breast Risk Gestational Dating (LMP)HIV PMTCT Protocol IOTA Simple Rules IVF Due Date & AMH Iron Deficit (Ganzoni)Labour Progress (WHO)Maternal Sepsis (qSOFA)O-RADS Classification Ovarian Cancer Staging PAS Hemorrhage Risk PPH Protocol (FIGO)Preeclampsia (ACOG)Rho(D) Dose (K-B)Rotterdam PCOS Criteria Syphilis Management TORCH Framework VBAC Success Probability Vulvar Cancer Staging Weight Gain (IOM)mWHO Cardiac Risk

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Clinical Notice:Calculations must be re-checked and should not be used alone to guide patient care, nor should they substitute for professional clinical judgment. OpiCalc is an auxiliary reference tool for qualified healthcare professionals.

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Rho(D) Dose (K-B)

Kleihauer-Betke guided Rho(D) Dose

Fetal Cells Counted

Total Cells Counted

Standard protocol includes adding one additional dose to the calculated count to account for sampling error.

Guidelines & Evidence

Verified

Last Review: 2026

When to Use

Primary Clinical Uses

Determining the exact number of Rho(D) immune globulin (RhoGAM) vials required for an Rh-negative mother after a massive Fetomaternal Hemorrhage.

Evaluating trauma, placental abruption, or complicated deliveries in Rh-negative patients.

Preventing severe alloimmunization (Hemolytic Disease of the Fetus and Newborn) in future pregnancies.

Why the KB Test?

The standard 300 mcg dose of RhoGAM only neutralizes 30 mL of fetal whole blood. If a massive abruption causes 100 mL of fetal blood to enter maternal circulation, a single vial will fail, leading to catastrophic sensitization.

Last Comprehensive Review: 2026