Doctors at the Mayo Clinic have upgraded the separated twins from ‘critical’, following their 12-hour operation, to ‘serious’. This means they are improving.

Doctors say the girls are right on course – their healing continues as hoped.

Last Friday, the two 5-month-old girls, Abbigail and Isabelle Carlsen, who were conjoined at birth, were separated by a team of 30 health care professionals. The girls were born with their diaphram, liver and pancreas attached – their heads facing each other. Part of their intestines were also shared, as well as a bile duct.

What Are Conjoined Twins?

There are two types of twins – Fraternal Twins and Identical Twins. Fraternal Twins come from two separate eggs (dizygotic), Identical Twins come from one egg (monozygotic), the developing embryo splits into two. Identical Twins look very much like each other, Fraternal Twins are as similar to each other as normal siblings are.

(Monozygotic = They result from the fertilization of one egg by one sperm
Dizygotic = They are the result of two eggs that are fertilized by two sperm)

Fraternal Twins can be the same or different genders – boy and boy, girl and girl, or boy and girl. Identical Twins are the same gender – only boy and boy, or girl and girl are possible.

Conjoined Twins are Identical Twins, but when the embryo starts to split, on the 13th day after conception, it does not do so completely – parts of the two stay stuck together. The two embryos mature into two fetuses that have parts of their bodies stuck to each other.

Female conjoined twins are much more common. For every pair of male conjoined twins born, three pairs of female conjoined twins are born. This is puzzling, because male identical twins are more common than female identical twins.

Between one in every 40,000 to 70,000 births are conjoined twins. Only one in every 200,000 live births are conjoined twins.

Conjoined twins are slightly more common in Africa and India than in the USA, Canada, or Europe.

40% of conjoined twins are stillborn, 75% are either stillborn or do not survive beyond their first 24 hours of life.

The term ‘Siamese Twins’ used to be common and had the same meaning as ‘Conjoined Twins’. Conjoined Twins became the standard term as it is less discriminatory.

Eng Bunker and Chang Bunker, from Siam

Siamese means ‘from Siam’. Siam was the old name for Thailand. The term Siamese Twins came after two Conjoined Twins from Siam who became famous. Eng Bunker and Chang Bunker were a circus attraction in the Barnum and Baily Circus, USA. They were joined at the chest. The twins were never separated, lived to the age of 63, both married different women and had 22 children between them.

Click on the link below for more information on Conjoined Twins
http://www.conjoined-twins.i-p.com

Written by: Christian Nordqvist
Editor: Medical News Today