Vaginal bleeding is the most common symptom of a threatened abortion. An incomplete abortion is when some of the pregnancy tissue remains inside a woman and is usually expelled over time. In some cases however the tissue may need to be removed by a health-care provider. During a complete spontanious abortion, all the tissue is expelled out of the body. There is no need to have any tissue removed after this type of miscarriage, although seeking medical advice during this time is recomended.
Inevitable abortion is when a miscarriage is imminent.
There is little warning and little signs to know. Tissue is also expelled. In a missed abortion, the fetus has died or did not develop. The pregnancy tissues have not been expelled from the uterus. With this type of miscarriage again there is little sign of what is happening until it has already happened.