What causes a miscarriage?

First trimester miscarriages are caused by chromosomal abnormalities in the fertilized egg. What does it mean? It means that the egg and sperm had the wrong number of chromosomes. As a result the fertilized egg cannot develop normally.

Miscarriage is also caused by problems that occur during the early development. The egg may not be implanted in the uterus properly. Or the embryo may have structural defects that prevent it from developing.

However, it is very difficult to tell why the pregnancy was lost.