title: Financial implications of RHD genotyping of pregnant women with a serologic weak D phenotype.
abstract: BACKGROUND
  Hemolytic disease of the fetus and newborn, classically caused by maternal-fetal incompatibility of the Rh blood group D antigen, can be prevented by RhIG prophylaxis. While prophylactic practices for pregnant women with serologic weak D phenotypes vary widely, RHD genotyping could provide clear guidance for management. This analysis evaluated the financial implications of using RHD genotyping to guide RhIG prophylaxis among pregnant females.
  
  
  METHODS
  A Markov-based model was constructed to evaluate the costs of RHD genotyping for pregnant females with serologic weak D phenotypes to inform RhIG prophylaxis. Using a comparison strategy of managing these women conservatively as D-, direct medical costs were assessed over 10- and 20-year periods for a simulated population of US women. One-way and probabilistic sensitivity analyses were used to assess the robustness of conclusions.
  
  
  RESULTS
  Using base-case variables, RHD genotyping for pregnant women with serologic weak D phenotypes is expected to marginally reduce overall costs. RHD genotyping these patients, rather than conservatively managing them as D-, would be cost-saving when the cost of genotyping is below $256. Genotyping would decrease net costs among non-Hispanic Caucasian females (-$0.17/pregnancy), but would increase costs among non-Hispanic African Americans (+$0.51/pregnancy), non-Hispanic American Indian/Alaskans (+$0.10/pregnancy), and Hispanics (+$0.37/pregnancy). Incorporating RHD genotyping would not significantly impact costs among Asians and Hawaiians/Pacific Islanders.
  
  
  CONCLUSIONS
  Using RHD genotyping to guide RhIG prophylaxis among pregnant women with serologic weak D phenotypes may be clinically beneficial without increasing overall costs.
authors: Department of Pathology, Johns Hopkins University, Baltimore, Maryland.
authors: Seema
authors: S
authors: Kacker
authors: National Molecular Laboratory, American Red Cross, Philadelphia, Pennsylvania.
authors: Ralph
authors: R
authors: Vassallo
authors: National Molecular Laboratory, American Red Cross, Philadelphia, Pennsylvania.
authors: Margaret A
authors: MA
authors: Keller
authors: Blood Group Genomics, New York Blood Center, New York.
authors: Connie M
authors: CM
authors: Westhoff
authors: Carey School of Business, Johns Hopkins University, Baltimore, Maryland.
authors: Kevin D
authors: KD
authors: Frick
authors: Department of Pathology and Laboratory Medicine, MedStar Georgetown University Hospital, Washington, DC.
authors: S Gerald
authors: SG
authors: Sandler
authors: Department of Pathology, Johns Hopkins University, Baltimore, Maryland.
authors: Aaron A R
authors: AA
authors: Tobian
mesh_terms: D000328:Adult; D003365:Costs and Cost Analysis; D004899:Erythroblastosis, Fetal / Q000191:economics / Q000235:genetics / Q000517:prevention & control; D005260:Female; D060005:Genotyping Techniques / Q000191:economics* / Q000379:methods; D006801:Humans; D008390:Markov Chains; D018803:Models, Economic; D011247:Pregnancy; D012204:Rh-Hr Blood-Group System / Q000235:genetics*; D014481:United States
chemical_list: D012204:Rh-Hr Blood-Group System; C026410:Rho(D) antigen