World has got so many miracles and amazing things which make the world complete. When it comes to the new born there are various kinds of babies possible which can be singleton, triples, twins and many more. Twins are one or may be two babies that are produced in one pregnancy. Multiple births are much rare in the case of human beings and can arise in various combinations and can vary based on genetic background and race. Twins does not mean looking alike there are so many varieties of twins. Here are the most popular 10 different kinds of twins.
10. Conjoined Twins
Conjoined are the identical twins that do not get separated completely from one another as the ovum is not divided completely and their bodies are stick to each other at the time of birth. These twins are connected with each other certain points of the body and they may share common limbs, amniotic sac, placenta, organ or tissue. They can be formed due to fusion and fission. In fission eggs that are fertilized do not split completely. In the case of fusion, eggs are separated fully but the stem cells get fused to keep the twins together.
9. Half Identical
This is the category of twins that are rarely formed and they can inherit same genes from their mother but different genes from their father. These twins are half identical and they can be monozygotic or dizygotic.
8. Monozygotic Twins
These are the twins that are formed out of a single fertilized egg. Single egg is split up into two different embryos. These embryos then lead to the formation of separate foetus. These twins are even known as identical twins as they share identical genes. They may not be identical perfectly but can be alike to certain extend. The differences that you find in these twins are due to the environmental factors. These twins can have identical DNA, same sex and personalities. They share similar placenta and have got amniotic sacs that are separate. These twins can also be known as maternal twins.
7. Dizygotic Twins
These are the twins that are formed out of two different fertilized eggs. These twins formed with the fusion of two eggs that get fertilized by two separate sperms and thus form different zygotes. In a normal case, women can release only a single egg during the ovulation cycle but at certain instances multiple eggs can also be formed which can lead to the formation of dizygotic twins. They do not have same genes. They are formed with the release of two or more eggs and when both of them get fertilizes. There are chances for them to be in similar sex or different. These twins have separate placentas and amniotic sacs.
6. Mirror Image Twins
These are the wins that are formed when the fertilized eggs take much time to get separated than the normal time. They have identical genetics but can have differences that of mirror image. DNA is same in them and some parts of their body gets mirrored. They can also get reversed asymmetry that includes mirror image dental structure, opposite handed and also personality traits in left brain and right brain. They can look similar but they look more identical when they stand facing each other. If the separation of the egg takes some more time, these twins could have become conjoined twins.
5. Parasitic Twins
These are twins also called as unequal conjoined or asymmetrical conjoined. One baby can be normal and the other one may have defects and so it depends on the cardiovascular system of the normal one. This happens when a twin that is under developed get attached to any of the body part of developed one. In most of the case it needs to be removed through a surgery.
4. Superfetation Twins
These twins are formed in such a context when one fetus is formed while the other one is already present in uterus. This is the situation that happens when the two cycles of menstruation can release eggs in the different way than that of normal zygotic twins. When the fertilization occurs in two different times in the same cycle it is known as superfecundation. This is something rarely found in human beings.
3. Heteropaternal Superfecundation Twins
This is the kind of twins formed out of fertilization of different eggs by different sperms in the same cycle. The second ova can be conceived within just few days or hours after first conception.
2. Twins with Various Birthdays
This happens when one twin is born prematurely and other remains in the womb to develop and thus grow.
1. Twins of Various Race
There are chances for the twins to be formed of various races, if the parents are mixed race. The possibility of a mixed race couple of obtaining twins of various colors are a million to one. If the twins are acquired from mixed race parents, one can possibly be white, fair-haired and also light skin and the further can be black and have darkish hair.