隨著台灣優生保健法的實施，孕婦產前檢查的落實，以及「墮胎」的合法化，使得產下畸型胎兒的家庭減少許多，但也衍生一個倫理議題：醫療專業人員應該尊重孕婦的「自主權」還是為畸型胎兒的「生存權利」代言？因此，本文從法律、宗教、文化等觀點論述畸型胎兒的生存權，並以Jonsen、Siegle與Winslade（2010） 提出的「四盒模式」（four-box model） 及倫理原則，分析一位已懷有連體嬰的母親是否終止妊娠之倫理決策。分析結果為：醫療團隊雖然尊重父母「繼續懷孕」的自主權，但卻難以預估連體嬰的出生造成其家庭的衝擊，不過我們能提供孕母以及畸型胎兒所需的護理措施以確保生產前後的安全與照護品質。

Families having fetuses with congenital abnormalities have decreased because of the Genetic Health Law legislated in Taiwan and the generalization of prenatal examination. However, an ethical issue needs to be addressed: healthcare professionals should respect the autonomy of pregnant women or advocate for the right of fetuses to survive with congenital abnormalities. This article critically reviewed law-related, religious, and cultural literatures. In addition, we used Jonsen et al. (2010) addressed "four-box model" and ethical principles to analyze the ethical decision-making process as to whether the mother with conjoined twins should terminate her pregnancy. In conclusion, although health professionals respected the parents' autonomy and did not proceed with pregnancy termination, it was difficult to predict the impacts of having conjoined twins' birth on the family. We provided necessary prenatal and postnatal nursing care for the mother and her fetuses with congenital abnormalities to assure their safety and quality of care.