How is missed abortion defined?

Missed abortion is specifically defined as a situation in which a fetus has died but remains in the uterus without being expelled. This can occur in the early stages of pregnancy and may not present with typical symptoms that would indicate a miscarriage, such as bleeding or cramping. Typically, the diagnosis is made through ultrasound, where the absence of fetal heart activity can be observed while the body has not yet recognized that the pregnancy has ended.

This definition is critical for understanding missed abortion because it highlights the unique aspect of the fetus being retained even after it has ceased to develop. In clinical practice, this condition often requires careful monitoring and may lead to medical or surgical intervention if the retention continues without the onset of a natural miscarriage.