Conjoined Twins

Erin Arnas, Joe Rising, Amanda Yackley, Lindsey Johnsen

What are conjoined twins?

Conjoined twins are two babies that are born connected by skin, organ, or body part.

These twins occur when an early fertilized egg doesn’t completely separate into two individuals in early development. Two babies still develop normally, they are just physically connected to each other. Conjoined twins may also share one or more internal organs and be connected this way.

A majority are stillborn, but some end up surviving and are able to be surgically separated. The success of the separation of the conjoined twins depends on where the twins are joined.

How do conjoined twins happen?

When identical twins are formed, a single fertilized egg splits and develops into two individuals. Then 8 to 12 days after conception, the embryonic layers that will split to form monozygotic twins starts develop into specific organs. If the embryo splits later than this like 13-15 days after conception.

If this happens separation stops before the process is complete, and the resulting twins are conjoined.

Another theory of how they are formed states that the two embryos may somehow fuse together in early development.

The cause overall is unknown. (Mayo clinic)

Conjoined Twins Throughout History

There have been many famous cases of conjoined twins throughout history. One set of twins was Eng and Chang Bunker from Thailand which was called Siam at the time, this term Siamese twins was coined in reference to these twins. This term is not considered appropriate anymore, because conjoined twins aren’t born to one single racial or ethnic group they are born all over the world. Eng and Chang later became business men and ranchers and married their sisters. They had 24 children ,and they died at the age of 63 in 1974. (UMM)

Eng and Chang Bunker

How are conjoined twins connected?

Conjoined twins can be joined in many places and are usually classified by the way that they are conjoined.

If they are joined at the chest which is one of the most common ways, they are classified as Thoracopagus twins. They often share organs such as the heart, liver and upper intestine.

How are conjoined twins connected?

If the twins are joined at the bellybutton they are called Omphalopagus twins. These twins will often share the same liver, sometimes these twins will share lower parts of the small intestine and the colon. These twins often do not share a heart.

How are conjoined twins connected?

If twins are joined at the base of the spine they are referred to as Pygopagus twins. These twins often face away from each other, and they will sometimes share the same GI tract. Less often they share the same genital and urinary organs.

How are conjoined twins connected?

If twins are joined at the pelvis they are called Ischiopagus twins. These twins will share the same GI tract, liver, genital, and urinary organs. Twins may have two legs or one pair of legs, but this is uncommon.

How are conjoined twins connected?

If the twins are joined at the head they are called Craniopagus twins: they share a portion of the skull and maybe brain tissue.

Separation of Conjoined Twins

Separating conjoined twins is a very risky procedure.

The mortality rate of the operation all depends on where the twins are conjoined and what organs they share. For example, if the twins are connected at the spine twins or pygopagus, then they have a 68 percent chance of a successful separation. If the twins share a heart there have been no known survivors to this surgery (UMM). Surgery has improved since the 1950’s in every separation.

At least one twin has survived the surgery 75% of the time. Even after separation paygopagus twins must go through a lot of rehabilitation due to malformations in the position of their spine. (UMM)

There have been many cases where separation of conjoined twins have been successful, one example is Angelica and Angelina who were fused together at the chest and abdomen. They share a liver. Thanks to modern technology, both the girls made it through the 10 hour operation.

Another case, Rital and Ritaj, were conjoined at the head. Upon delivery their heart was already failing and emergency separation surgery had to be done. If there was a significant drop in blood pressure during the surgery there could have been brain damage, but both the twins seem healthy and alert.

Success Rates

“Success” = when at least 1 twin survives

Highly depends on what kind of conjunction.

Sacrum: 68% survival

Heart: no known survivors to date

Since 1950, success rate has improved to 1 twin surviving at least 74% of the time

To date, there has been 250 successful separations in the world.

Still Conjoined

Abby and Brittany Hensel, are conjoined twins from New Germany, Minnesota. They are now 25 years old and live a relatively normal life even though they both are only able to control one half of there body so they must coordinate movements. But they still can walk, run, bike and drive. They can even type on a keyboard at the same speed as a normal individual. Their scenario is extremely rare however.

Abby and Brittany

Social Implications

Some parents don’t want to risk losing their children.

Psychological effects: separation affects them socially because they don’t have the other twin with them all of the time.

If one twin survives and the other doesn’t, the surviving twin may experience guilt.

Sexual Reproduction varies depending on where they are conjoined. This can get a little complicated.

Life together when conjoined: spending all of their time together.

Political Implications

The legal issue depends on the health status of the twins, some courts will rule to save one twin over the other.

Voting

Drivers licenses

Ethical Implications

This is a life and death decision, and sometimes it is necessary to sacrifice one twin in hopes of saving the other.

There is very high risk, and they are dangerous surgeries. Doctors may question if it is right or not.

Should separation be attempted?

Video

https://www.youtube.com/watch?v=Ucxen4x_uV0

Sources

Galleger, James. "Separating Conjoined Twins Rital and Ritag: The Journey - BBC News." BBC News. BBC News, 19 Sept. 2011. Web. 16 Nov. 2015. <http://www.bbc.com/news/health-14969823>.

Jaslow, Ryan. "Once-conjoined Twins Angelica and Angelina Thrive Six Months after Operation." CBSNews. CBS Interactive, 1 May 2012. Web. 16 Nov. 2015. <http://www.cbsnews.com/news/once-conjoined-twins-angelica-and-angelina-thrive-six-months-after-operation/>.

"Facts About the Twins." University of Maryland Medical Center. University of Maryland Medical Center, n.d. Web. 11 Nov. 2015. <http://umm.edu/programs/conjoined-twins/facts-about-the-twins>.

Mayo Clinic Staff. "Conjoined Twins." Treatments and Drugs. Mayo Clinic, n.d. Web. 11 Nov. 2015. <http://www.mayoclinic.org/diseases-conditions/conjoined-twins/basics/treatment/con-20029293>.

Reporter, Daily Mail. "School, Shopping, Sunbathing ... Normal Activities in an Extraordinary World: Conjoined Twins Abigail and Brittany Hensel Offer a Glimpse in to Their Lives in New Reality TV Series." Mail Online. Associated Newspapers, 30 Aug. 2012. Web. 11 Nov. 2015. <http://www.dailymail.co.uk/femail/article-2195220/Conjoined-twins-Abigail-Brittany-Hensel-offer-glimpse-extraordinary-world.html>.