Kinds of twins with their own uniqueness

So far, of course, you only know identical twins and gender twins. However, did you know there are various other types of twins on this earth? Let's see, what kinds of twins are unique in this world.

Kinds of twins

1. Siamese twins

Conjoined twins are a condition when the monozygotes (the result of the fertilization of the sperm and egg) are not completely separated. This separation of the divided cells occurs because the ovum cells do not completely divide by themselves.

Later, conjoined twins have one part of the body that is connected to each other, whether it's body tissues, organs or even other limbs.

2. Superfetation twins

These kinds of twins are quite rare, and they are not twins. How come? Yes, superfetation twins occur when a pregnant woman ovulates or releases an egg. If during ovulation the mother and partner have intercourse and sperm cells are released, fertilization can occur more than once.

So that, later the mother will have more than one fetus produced from different sperm and egg cells. Because of the different fertilization processes, there is an age range between the fetuses. The age of the fetus can be different in days or weeks according to the time of fertilization, and it can also be born at the same time.

3. Twin different fathers (superfecundation)

Different paternal twins are dizygotic twins (two different sperm cells and two eggs) that result from hyperovulation. This occurs when more than one egg is released by a woman's body.

The first egg is fertilized by the first man, and after a few days or time later the second egg is fertilized by a different man again. These twins are also commonly referred to as superfecundated twins. Later the physical condition (hair, skin, eye color) of the two babies born can be different because the sperm are different.

4. Different gender identical twins

Identical twins that occur from the fertilization of one sperm and one egg. Generally these types of twins have the same sex. This is because they are formed from the same fetus containing male (XY) or female (XX) sex chromosomes.

However, in the case of different sex twins, there are several cases of genetic mutations that cause male fetuses to become twins, one of which loses the Y chromosome and develops.

Later, the fetus that loses the Y chromosome will develop into a female fetus. The risk is that twin girls born can have Turner syndrome, which is characterized by a short stature and a lack of ovarian development.

5. Mirror twins

Other kinds of twins are mirror twins. This occurs when a sperm cell and an egg successfully fertilize and divide into two. In the case of mirror twins, the cleavage process can be very slow (it can take more than 1 week). In addition, during the slow division process, the future twins can develop and grow in reverse asymmetry, just like you are looking in a mirror.

Later, after birth, there may be one child who is left-handed and one who uses an ordinary right hand. There are also children who may have birthmarks on the opposite side of the body. In theory if the twins were facing each other, they would appear as mirror reflections.

6. Parasitic twins

Parasitic twins are conjoined twins, one of which does not develop normally. Then, the twins that did not develop normally stop growing and are still attached to the twins. They are called parasitic twins because these undeveloped twins usually take their blood intake from their perfect twins.

7. Twins with different races

This condition occurs in fertilization that occurs in two different eggs, where twins can be born with different physical characteristics according to race.

In 2005, an inter-racial couple in England gave birth to two female twins with the physical characteristics of the first child having blonde hair and light skin, and the other having dark hair and skin according to their parents' different races.

Apart from natural fertilization (getting pregnant from sex), this type of twins of different races can also occur through the IVF (In Vitro Fertilization) procedure.