• ethics
• neonatology
• twins

Twenty years ago, clinicians were faced with an agonising decision; whether the proposed separation of conjoined twins was lawful. A court decision was necessary. The parents opposed the separation because the operation would lead to the immediate death of one of their twins. This dilemma could re-emerge at any moment, so the decision merits study.

The case, Re A,1 concerned Jodie and Mary, born to devout Catholic parents. The girls each had their own brain, heart, lungs and vital organs; and each had four limbs. But the court was told that Mary’s cardiorespiratory system was insufficient to support life; she remained alive only because of their connected circulations. Jodie’s aorta supplied that of her sister; and their inferior cavae were distally united into a common channel. If Mary had been born as an independent baby, she would not have lived after cessation of placental circulation.

Without separation, the surgeons predicted that Mary would die within 3–6 months, followed within hours by her sister, who would exsanguinate into her dead sister’s circulation. Surgical separation in the neonatal period was feasible in that Jodie would be able to live a relatively normal life, but Mary would die within minutes of the division of the aortic connection. Their parents opposed the operation, believing their children’s fate should be left to God; and that killing Mary was wrong.

The clinical staff recognised that they were confronted with a decision for which they were at …