A blighted ovum is characterized through ultrasound by the absence of an embryo (anembryonic pregnancy). This means that the egg does not develop fully into a baby. Blighted ovum are associated with a high incidence of chromosomal abnormalities. This condition seems to occur more often in older women.

Statistics suggest that around 60% of first trimester miscarriages are due to chromosomal abnormalities unique to that pregnancy. Usually the chromosomal abnormality lies in the individual egg. The chances of having another blighted ovum are not increased due to having a previous blighted ovum.

Repeated cased of a blighted ovum may indicate a genetic or physical disorder in the parents. Low hormone levels can also be to blame in a small percentage of cases.

If the miscarriage does not happen spontaneously, the doctor may suggest a D & C (dilation and curettage) in order to lessen the trauma of having to wait for it to happen naturally.