【Objective】 To comprehensively explore the serological characteristics of anti-PP1Pk and potential therapeutic strategies for recurrent miscarriage in p-blood type pregnant women. 【Methods】 Neutralization with pigeon egg white and human plasma, disruption of IgM antibodies by 2-mercaptoethanol reagent, and complement adding were conducted. Anti-PP1Pk titers under different processing conditions, media and temperatures were determined, and neutralizing effect of human plasma on anti-PP1Pk and its sensitization complement ability were analyzed. 【Results】 The titers of anti-PP1Pk in saline and column agglutination were 4 and 8, respectively. Low temperature increased titers, while β-mercaptoethanol treatment significantly reduced them. Pigeon egg white partially neutralized anti-PP1Pk antibodies. Human plasma was also capable of reducing anti-PP1Pk titers with neutralization capability surpassing that of pigeon egg white, and there were individual differences in neutralization capability. 【Conclusion】 The anti-PP1Pk was a blend of antibodies encompassing both IgM and IgG types, exhibiting cold reactivity, and having the potential for complement activation. Human plasma emerges as an effective modulator for diminishing the efficacy of anti-PP1Pk. Plasma transfusion holds promise as a therapeutic avenue for addressing recurrent miscarriages in pregnant individuals with the p phenotype.