產後憂鬱是影響婦女健康，且攸關家庭幸福安寧的重要議題。研究證實其可能改變親子依附關係、配偶關係及使家庭功能出現障礙。雖然產後憂鬱的現象非常常見，但是產後憂鬱概念易與其他相關概念（如產後沮喪、產後精神病）混淆，繼而影響適切的預防與處置，因此本文依據Walker及Avant（2011）的概念分析法，界定產後憂鬱的定義性特徵及其發生的前因與後果，提供實證性的篩檢工具，且列舉典型、邊緣與相反案例以和其他相關概念作區別。結果發現產後憂鬱的定義性特徵為：（1）起始時間及持續時間為產婦生產後四到六週開始，持續超過兩週以上；（2）產婦出現憂鬱症狀達五種（含）以上；（3）影響產婦的社會功能，如照顧孩子的能力不夠、無法集中精神處理日常事物等。本文旨在增加護理人員辨識產後憂鬱的能力，以提早發現產後憂鬱的現象，提升產婦及其家庭成員的照護品質。

Postpartum depression (PPD) affects the health of women and is an important issue that impacts negatively on the happiness of affected families. Previous studies have demonstrated that PPD impairs the mother-child attachment, impacts the marital relationship, and may cause family dysfunction. Although PPD is a common phenomenon, the concept of PPD is easily confused with other similar concepts such as postpartum blues and postpartum psychosis, which may delay proper prevention and management. This paper identifies the definitions, characteristics, antecedents, and consequences of PPD as well as provides empirical screen measurements and examples of model, borderline, and contrary cases in order to differentiate between the concepts of PPD and other disorders using Walker and Avant's (2011) concept analysis methodology. Three defining characteristics of postpartum depression were identified. First, depression begins four to six weeks after delivery and continues for at least two weeks. Second, we benchmarked over 5 depressive symptoms. Third, postpartum depression may disrupt puerperal women’s lives by making it difficult for them to care for their babies and to concentrate on daily tasks. We hope that this article enhances nurses' professional competences to detect PPD as early as possible and to promote the quality of care received by postpartum women and their family members.