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Rh negative vs. Rh positive

[ahr-eych neg-uh-tiv] / ˈɑrˈeɪtʃ ˈnɛg ə tɪv /
Or Rh-negative

adjective

  1. Rh factor

[ahr-eych poz-i-tiv] / ˈɑrˈeɪtʃ ˈpɒz ɪ tɪv /
Or Rh-positive

adjective

  1. Rh factor