Conjoined Twins, The term Siamese twins originated from the famous conjoined twins Chang and Eng Bunker (1811-1874) who was born in Siam (now Thailand). The case of conjoined twins are the oldest recorded Chulkhurst of Mary and Eliza who was born in England in 1100's.
Causes Birth of Twins
Many of the factors blamed for twin pregnancies. In addition to genetic factors, fertility drugs are consumed in order to perfectly cooked eggs, also thought it would trigger the occurrence of twins. The reason is, if the ovaries can produce eggs and given fertility drugs, then the egg is cooked at the same time can be considerable, even up to five and six.
Broadly speaking, the twins were divided into two. Monozygotic, twins are derived from one egg and dizygotic twins from two eggs. Of the total number of multiple births, one third are monozygotic. Dizygotic twins means two mature eggs at the same time, and then fertilized by sperm. As a result, the second egg is fertilized in the same time. While monozygotic twins means one egg is fertilized sperm, then split in two. Period of division is what will affect the baby's condition later.
The period of egg cell division is divided into four time, ie 0-72 hours, 4-8 days, 9-12 and 13 days or more. In the first division, will occur diamniotic the uterus has two membranes, and dichorionic placenta or the uterus has two. While in the second division, the membranes remain two, but the uterus had only one placenta. In this condition, it could happen one of these babies get a lot of food, while the baby is not attached. As a result, infant development could be hampered. Then, in the third division, placental membranes and each only a, but the baby is still split as well.
In the fourth division, the uterus has only one placenta and one amniotic membrane, so the possibility of conjoined twins is quite large. Because of time pembelahannya gradually, so that the trigger-packed eggs. So conjoined twins usually occurs in monozygotic that pembelahannya more than 13 days.
Of the four divisions, of course it is best to first division, because the baby could split perfectly. However, fourth division can not be timed. Factors affecting the division of time, and why could split the resulting imperfectly attached, usually associated with infections, malnutrition, and environmental problems.
The division of types of conjoined twins
Siamese twins themselves are mostly female, divided into several types of cases, based on the position of attachment of both.
Of all twin attached, attached mostly occurred in four limbs, the chest as much as 40 percent, 35 percent of the abdomen, pelvis and head 12 per cent between six and ten percent.
There are several types of conjoined twins:
Thoracopagus: two bodies united at the chest (thorax). The heart is always involved in this case. When only one heart, life expectancy with or without surgery is low. (35-40% of all cases)
Omphalopagus: two bodies united at the bottom of the chest. Generally, each body has the heart of each, but usually this type of conjoined twins have only one heart, digestive system, diaphragm and other organs. (34% of all cases)
Xiphopagous: two bodies united at the xiphoid cartilage.
Pygopagus (iliopagus): united in the rear. (19% of all cases)
Cephalopagus: united in the head with a separate body. Conjoined twins of this type generally can not survive because of serious abnormalities in the brain. Also known as janiceps (for a two-faced god Janus) or syncephalus.
Cephalothoracopagus: Body united in the head and thorax. This type of conjoined twins is generally not survive. (Also known as epholothoracopagus or craniothoracopagus)
Craniopagus: skull bones are united by a separate body. (2%)
Craniopagus parasiticus - a second part of the head has no body.
Dicephalus: two heads, one body with two legs and two or three or four arms (dibrachius, tribrachius or tetrabrachius) Abigail and Brittany Hensel, conjoined twins is an example of the United States types dicephalus tribrachius.
Ischiopagus: conjoined twins united anteriorly at the bottom of the body. (6% of all cases)
Ischio-omphalopagus: Conjoined twins are united with the spine forming the letter-Y. They have four arms and usually two or three feet. This species usually has one of the reproductive system and exhaust system.
Parapagus: Conjoined twins united in the lower body with a heart that is often divided. (5% of all cases)
Diprosopus: One head with two faces in the opposite direction.