Sometimes an embryo splits after fertilization into two. This makes identical twins. When the embryo splits, but remains attached to the other, you get conjoined twins.
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Conjoined twins are babies joined at birth.
Conjoined twins
If you are referring to conjoined twins, than they are formed by an egg that partially splits when developing in the uterus.
just that they are conjoined, or joined together by a body part. if they are conjoined at the head, it could causes brain damage and depending on how much of a brain they share they will have to do surgery and during the surgery one of the babies will die. if it is not too severe, a quick separation won't do anything, but could causes mental problems during birth. i am not sure what happens by being conjoined at the heart, though. i think that is either impossible, or the baby(ies) is born dead.
The twins were conjoined when they were born.
They were such good friends it was like they were conjoined at the hip.
Conjoined children can be connected at any body part. So yes, they can be conjoined by testicles.
Depends on how they were conjoined.
conjoined twins are very very very rare .
Conjoined twins cannot be bred. This condition is not genetic.A set of male conjoined twins fathering children with a set of female conjoined twins will almost certainly produce children who are not even twins at all.
why can't conjoined twins be brothers and sisters