Fraternal and Identical Twins

Not all twins act the same, even the ones that are identical. They may come about the same way. Fraternal and Identical Twins have some of the same traits but are definitely not the same. All twins, whether fraternal or identical, are truly two separate unique individuals.

There are four different types of twins. The first is fraternal twins that either never divided or divides within the first four days and have two separate amniotic sacs and placentas. This is included for almost all fraternal twins. The second is Identical twins that share the same placenta, but have two amniotic sacs.

This occurs when the embryo splits in 4-8 days and is most likely to occur in 60-70% of all identical twin pregnancies. The third is also identical twins that share the same amniotic sac and appear when the embryo splits after 9 days.

The last and most uncommon type of twins are the conjoined twins, which occurs when division takes place later than 12 days after fertilization. This can cause the embryo’s to become joined together on some part of their body. Identical Twins are most unique. They are the most admired and sometimes the most notable.

It is believed by most that this is the most common type of twin. This is not a proven fact because fraternal twins have become the norm, while identical twins have become somewhat of rarity. There are 3 different ways that identical twins can develop and be carried:

The first case is where there is only one placenta that feeds the babies, but there can be two amniotic sacs. When there is 1 placenta and 2 amniotic sacs then the pregnancy is referred to as having an identical pregnancy. Twins may also occur from invitrofertilization.

This is when several fertilized eggs are placed inside the mother, with the hope of one of them becoming an embryo. This can sometimes lead to one or more of the eggs becoming an embryo. Identical twins share a single egg but are fertilized by one sperm. The egg splits into two identical halves.

This usually takes place within the first few days of fertilization. Identical twins share the same DNA and are always the same sex and same blood type. However, they do not have the same fingerprints. This is somewhat a shocker since most of the TV detective shows often portray identical twins that are identical in every way.

Scientists believe that the reason that this is not prevalent is because they often don’t have the same exploratory pattern as the opposite twin. While in the womb, they do share the same placenta. Identical twins are similar in appearance and are relatively easy to tell apart.

They also seem to occur randomly, three out of 1000 births. This is why they less common as fraternal twins. Fraternal twins come about when a woman releases two separate eggs at the same time. The eggs are fertilized by two separate sperm. Fraternal twins can be the same sex and blood type.

They have become more common among older women over the age of thirty-five. There is still a lot of research as to why this is so for mature women. Fraternal twins also have separate placentas and don’t share the same of anything. They have the most distinct features but you can be able to tell them apart.

Some of the most recognizable fraternal twins would be Mary-Kate and Ashley Olsen. They look identical but are fraternal twins who look so much alike in appearance. This can cause the person with keen eyes to be easily deceived into thinking that they are identical twins.

Scientists also think that fraternal twinning may be due to hereditary influences. It has been studied that more women commonly have several sets of fraternal twins throughout many generations in the family. It is a common misconception that twins only come from the mother’s side.

This is found only to be true when the father is the one with twins in the family or is a twin himself. The male’s parent can have several sets of twins and still may not be in indicator as to where they will actually have twins themselves.

The male only provides the sperm. The female is the only one who releases two eggs at the same time. This is where the mother’s genes become the one that has created the twins. The female can inherit the gene from the grandmother or aunt on her father’s side. Some people have the misconception that the mother inherits the twin gene from the mother’s side. Clearly, this isn’t the case. It also is more common in women of African descent to have twins and less in women of Asian descent. It is easier to tell the differences after the twins are born.

Fraternal twins are about as alike as a brother and a sister. Most people have heard or even actually seen an episode of Maury Povich where some women are certain that their fraternal twins share the same father. It becomes a shocker when Maury announces that one man “is the father” of one child, while he is not the father of the other. Talk about a jaw dropper. That means that the mother had sex with two different men, in a small time frame. Development issues can also indicate whether your babies are twins or not.

Identical twins usually have very similar developmental patterns. They do things often within days of each other, which means you might see them speaking and walking at different times but within days. Fraternal twins may have wide differences in these patterns.

There may be one twin who is equal to the developmental stage that is recommended at their age and the other one who may  need a little more time to grow. This doesn’t mean they will have developmental issues down the line but rather they need more time to develop.

In conclusion, fraternal twins are composed of two separate eggs and sperms, while identical twins come from the same fertilized egg that has been split in two. Fraternal twins vary in their appearance, while identical twins tend to look the same.

Fraternal twins may grow at different rates, but identical twins will follow the same pattern of growth. It almost makes you wonder if what researchers believe to be true, everyone is born with a twin. If that is the case, there are one more of you running around the world. This could be a good or bad thing, which are you?

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Fraternal and Identical Twins. (2016, Jul 18). Retrieved from https://phdessay.com/fraternal-and-identical-twins/

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