Types of Twins

Monozygotic
or identical twins result from a single fertilized egg that divides into separate halves and continues to develop into two separate, but identical babies. Identical twins are identical genetically. They share the same physical characteristics meaning they are the same sex, have the same hair and eye color and also have the same blood type.

Dizygotic
or fraternal twins derive from two eggs that are fertilized by two separate sperm. These twins may or may not be the same sex.