Final answer:
Miscarriage refers to the loss of a fetus before 20 weeks of gestation, which is distinct from abortion, a voluntary termination. Fetal viability is a key legal consideration, with better survival rates for babies born after 26 weeks. A fetus develops from weeks 8 to 38 after fertilization, with gestation lasting roughly 40 weeks.
Step-by-step explanation:
Miscarriage is the naturally occurring loss of a fetus prior to 20 weeks of gestation. This is considered a spontaneous termination of a pregnancy and occurs when the fetus cannot develop properly, leading to a natural conclusion of gestation. In contrast, a voluntary termination of a pregnancy is known as an abortion. The notion of fetal viability is crucial here, as laws often rely upon whether the fetus could survive outside the uterus. For instance, while some babies born at 23 weeks of gestation may have a survival chance with intensive care, the odds increase significantly after 26 weeks.
A fetus is considered a prenatal human organism between the embryonic stage and birth, which generally spans from weeks 8 to 38 after fertilization. The gestation process is divided into three trimesters, with the fetus developing critical organ systems and increasing in size and weight leading up to birth around 40 weeks.