Take for instance a woman gives birth to one girl and two identical boys. How does this happen?

Question

I suppose you could call them fraternal triplets collectively. Anyway, what is superfetation and superfecundation ?

Answer 1

It's like both different types of twins in one birth. There are 2 fertilized eggs, and one of the eggs divides into 2 fetuses. Here are the definitions of superfetation and superfecundation:

http://en.wikipedia.org/wiki/Superfetati...

Answer 2

When the woman ovulates, her body releases eggs and in order to become an embryo (or eventually a baby) the egg has to be fertalized. With twins, identical twins mean the same egg split apart. For faternal twins, it means two eggs were fertalized. In the case of triplets, one girl and identical boys, two eggs were fertalized, but the second egg split. Making the boys identical.