What causes an ethical dilemma in healthcare?

Many ethical dilemmas arise in health care.

A patient may be terminally ill, but you are not sure - do you tell him her of your suspicion or wait for test results, even though fast action might help the patient survive?

Abortion - pro life / pro choice? Is a mass of cells life blessed by god, or is it just that: a mass of cells?

Euthanasia? Is it a patients right to choose?

Stem-cell research (see abortion controversy)..

Many many more....