Usually, we see twins in our surroundings. Twins brother and sister, and sometimes only brothers and only sisters. But have you noticed that some of the twins are too much identical that they can't be differentiated, and some are too different that they don't look like twins?
Do you know how twins are formed? And why some twins are identical, and some are different, here we will discuss.
Normal Fertilization
Usually, an adult woman releases one egg from one of two ovaries every month. After releasing an egg from the ovary, it is caught by finger-like projections of the fallopian tube called fimbriates. The egg then inter into the fallopian line. Millions of sperms from vigina to uterus travel towards the egg in the fallopian box. From millions of sperms only one sperm succeed to fuses with the egg. After the fusion of egg and sperm, fertilization occurs. Now the structure formed after fertilization is called a zygote. This is regular fertilization.
In the case of twins, the situation is different. They are two types of twins; identical twins or monozygotic twins and fraternal or dizygotic twins.
Identical twins
Identical twins are also called monozygotic twins. In the case of identical twins, the fertilization is regular. Only one egg fuse with one sperm and form a single zygote.
But the zygote when undergoes the stage of cleavage. Due to hormonal imbalance, the two cells formed as a result of the first cleavage get separated. Each cell act as a separate zygote because each cell can create a complete embryo. So, in this case, two babies are produced, but they share the same placenta and become identical because they are formed from single fertilization.
Fraternal twins
In the case of fraternal or dizygotic twins, fertilization is not regular. Due to hormonal imbalance or some other issues, the female releases two eggs. Sometimes the eggs are released by a single ovary, or sometimes, both ovaries release one egg. The sperms are present in several million, so two different sperms fertilize both eggs.
In this case, two separate zygotes are formed, and each zygote develops a different baby. In this type, the twins become different from each other.
Test tube baby
The process of test tube Babies' production is called in vitro fertilization. Test tube babies are produced when females can't conceive. This happens due to the issue of fallopian block tubes or any defect in the ovaries of females.
The problem can also be in males. In males, it can be due to sterility and immotility of sperm.
In this case, the couple goes for a test tube baby. In a test-tube baby, the male and female gametes are extracted and are fertilized outside the body.
Procedure
In the first step of in vitro fertilization, the number of eggs are removed from the female body and are placed in a test tube in a laboratory. The sperms are extracted from the male body and are placed in the test tube with eggs for fertilization.
The zygotes formed as result fertilization are checked. The zygote with normal cell division is selected and put in the female's uterus.
In this case, the chance of twins is also there. The complete development of the baby occurs in the uterus. The Fragrance is then checking through a blood test.
You must be logged in to post a comment.