What term refers to the premature termination of pregnancy when the embryo or fetus cannot survive independently?

The term that refers to the premature termination of pregnancy when the embryo or fetus cannot survive independently is substantially covered under the definition of abortion. Abortion generally indicates the intentional or spontaneous end of a pregnancy before the fetus can live outside the womb. Although the term covers both induced and spontaneous cases, in a medical and clinical context, it is often used to describe situations where the pregnancy does not go to term due to fetal conditions that prevent survival.

While stillbirth denotes the loss of a fetus after the 20th week of pregnancy when it would have been viable, and miscarriage typically refers to the loss of a pregnancy before the 20th week, these terms highlight different aspects of pregnancy loss rather than the specific concept of termination when the fetus cannot survive independently. Prenatal loss is more of a general term relating to any loss during pregnancy and does not specifically capture the context of termination due to fetal viability.

Thus, within the context of the question, abortion encompasses circumstances of pregnancy termination related to fetal conditions, making it the most appropriate choice.