One woman desperately needs a kidney transplant; her husband wants to donate but is incompatible. Across the country, the same scenario. But the healthy spouses match the unhealthy spouse in the other couple and make a reciprocated donation to a stranger. About 230 such swaps have taken place since 2000, reports the Journal, and there's hope that the practice might ease organ shortages.
Experts estimate that swapping could add up to 4,000 transplants a year to the current 6,400 involving live donors, and docs are scrambling to create a national database. But surgeons are often territorial, and the system favors recipients who already have donors—leaving those on the deceased-donor waiting list behind, for an average of 5 years.