monotsygoottinen

Monotsygoottinen refers to a type of twin that originates from a single fertilized egg. This egg, called a zygote, splits into two embryos at a very early stage of development. As a result, monotsygoottinen twins are genetically identical, meaning they share the same DNA. This is why they are often called identical twins.

Because they come from the same zygote, monotsygoottinen twins will always be of the same sex. They will also share a very high degree of similarity in their physical characteristics, such as eye color, hair color, and facial features. However, while their genetic makeup is the same, environmental factors and random developmental variations can lead to subtle differences between them.

The timing of the zygote's split can influence certain aspects of the twin pregnancy. If the split occurs within the first three days after fertilization, the twins may develop separate amniotic sacs and placentas. If the split occurs later, between days four and eight, they might share a placenta. If the split occurs even later, after day eight, the twins may share both a placenta and an amniotic sac. This latter scenario, known as monoamniotic twins, carries a higher risk of complications.

The incidence of monotsygoottinen twins is relatively low, occurring in approximately 0.3% to 0.5% of all pregnancies. Unlike dizygotic twins (fraternal twins), which arise from two separate eggs fertilized by two separate sperm, the occurrence of monotsygoottinen twins is not thought to be influenced by factors like maternal age or fertility treatments.