A possible relationship between birth month and ABO blood type.
D000017:ABO Blood-Group System; D001789:Blood Group Antigens; D005826:Genetics, Medical; D006801:Humans; D007518:Isoantibodies; D010507:Periodicity; D012621:Seasons; D013223:Statistics as Topic
D000017:ABO Blood-Group System; D001789:Blood Group Antigens; D007518:Isoantibodies