Twins are formed when a woman's body releases more than one egg during ovulation, or when a single fertilized egg splits into two. This results in the development of two babies in the womb.
Here's a breakdown of the two main ways twins can be formed:
1. Fraternal Twins (Dizygotic Twins)
- Formation: When two separate eggs are released and fertilized by two different sperm.
- Characteristics: Fraternal twins are not genetically identical, just like any other siblings. They can be the same or different sexes.
- Frequency: This is the most common type of twin pregnancy, accounting for about two-thirds of all twin births.
2. Identical Twins (Monozygotic Twins)
- Formation: When a single fertilized egg splits into two embryos.
- Characteristics: Identical twins share the same DNA and are always the same sex.
- Frequency: This type of twin pregnancy is less common than fraternal twins, accounting for about one-third of all twin births.
While the exact reasons for the increased occurrence of twin pregnancies are not fully understood, factors such as age, genetics, and assisted reproductive technologies are believed to play a role.
