權衡 胎兒 婦女身體自主權 衍生性主張 超然性主張 滑坡效應 生命的挫折 生命神聖性 基本權利衝突 基本權利剝奪 法律工具主義 Weighing Fetus The right of women's body self-determination Derivative claim Detached claim Slippery slope Life's frustration Sanctity of life The conflict between constitutional rights The deprivation of the constitutional rights Legal instrumentalism