By: Aimee Mathers

A Brief Outline•Facts about twins

•What is TTTS?

•What causes TTTS?

•How does TTTS occur? And how often?

•Symptoms

•The Recipient Twin

•The Donor Twin

•How is TTTS detected?

•Treatments

•There are two main categories of twins. Fraternal and Identical.

•What are Fraternal twins? Fraternal twins occur when the mother releases 2 eggs during one ovulation cycle and these are then fertilised.

•the result of separate eggs becoming fertilized resulting in two completely different fetuses in the womb at the same time. They are known as non-identical or dizygotic twins.

•What are Identical twins? Identical twins occurs when a single conception splits into two around the same time the fertilized egg is becoming implanted in the womb ( Usually between the fourth and the twelfth day of conception).

•Twins that get to 37 weeks in the womb are considered full term, however the average weight at term for twins is slightly lower than the normal weight of a single baby.

•Twins are usually both delivered by a C-Section, although in some instances if the first baby to be delivered is not in a breech position the first baby may be delivered vaginally, and the second baby delivered by a C-Section.

• Genetic factors do not appear to have much affect upon

the incidence of identical twins.

•Identical twins exhibit almost identical brain wave

patterns.

•The term “twins” was derived from the ancient German

word twin or twine meaning “two together”.

•If the mother herself is a fraternal twin, the chances of

having twins increases about five-fold.

•Twins have been known to develop their own “language”

that only they can understand. This process is known as

“Cryptophasia”.

Left: TTTS with diamniotic/monochorionic twins which are discordant for size but have preserved amniotic fluid.

Right: Classic "stuck twin" with oligohydramnios in the donor twin sac and polyhydramnios in the recipient twin sac

TTTS stands for Twin To Twin Transfusion syndrome. It is a condition that may occur in identical twins or higher multiple pregnancies. The disease results when blood passes disproportionately between one baby and another through connecting blood vessels in their shared placenta. The babies are normal. The abnormalities are in the placenta.

This is Brennan. This picture was taken at 18 weeks. At this point Brennan was very small and was measuring in about 2 weeks behind Alex in development. You can see how thin his chest and abdomen are because he was not being nourished as well as his brother. That is one of the signs of Twin-to-Twin Transfusion Syndrome. The dark area around him is his amniotic fluid. As you can see here, he didn't have much, even though we had undergone two amino reduction treatments by this point.

This is Alex. This picture was taken at 17 weeks. He was swallowing. He looks like a normal fetus at 17 weeks along.

No one really knows why embryos split into identical twins or why TTTS occurs. However, we do know that if the embryo splits after four days a particular type of identical twin pregnancy occurs known as monochorionic. Most TTTS pregnancies are monochorionic diamnionic which means that the two fetuses share a placenta and individual amniotic sacs.

TTTS strikes about 10% of all identical twin pregnancies. In the U.S. alone, it affects over 7,500 babies, or 3,500 pregnancies each year. The Death rate for twins who develop TTTS at mid-pregnancy may be as high as 80- 100 %.

•Identical twins or higher multiple pregnancy including a set of identicals

•Excessive amount of amniotic fluid

•Sudden and excessive weight gain in mother

•Swelling of mother’s body

•Premature contractions

•Bleeding

The recipient Twin is receiving too much blood because some of the blood vessels of the other baby in the placenta split. These vessels cross their shared placenta over to the recipient twin. Because the recipient twin is getting their own blood plus the extra blood, they become larger in size. This is one of the first signs of TTTS. This blood is very thick like syrup and because it is much thicker than normal blood the heart has to work extra hard to pump the blood along. Because of the extra blood, the baby is urinating a lot. Amniotic fluid is generated by the baby urinating. This causes the recipient twin to have too much amniotic fluid and will need to have some removed as often as needed.

The Donor twin is much smaller in size and is often called the “stuck twin”. This baby is getting too little blood because half of the blood that it is suppose to be getting is going to the other twin. This baby isn’t getting very much blood, and is therefore not urinating much. Because of this, there is very little fluid in their amniotic sac. When born, it is often the donor twin who does better, because their hearts are not as tired. Their heart had it easy. Their heart hadn’t been over exerting itself to pump any extra blood. It didn’t have to pump much blood at all.

A Donor twin born prematurely.

TTTS is detected through an ultrasound (sonogram). It is critical to have routine ultrasounds during your pregnancy with multiples. It is also essential to look for differences in weights of the babies and to watch closely to make sure there are no drastic changes in the weights of the babies.

There is a new laser technology surgery that dramatically alters the odds for babies with TTTS. This is performed by inserting a fetoscope and laser fiber (about half the size of a yellow pencil), into the mother’s womb identifiying the offending connections and shooting them with the laser to destroy them.In 90% of the cases where the operation is performed, at least one twin survives and in 68% both twins live. Less than 2% of the babies who survive have any disabilities or birth defects, compared to up to 30% with other less affective treatments. This is one of few treatments out there right now for TTTS. It is a very successful treatment.

In my Presentation Of TTTS (Twin to Twin Transfusion Syndrome) I have explained a little about the kinds of twins you can have in a pregnancy, and how TTTS only occurs in Identical twins. I explained what TTTS was, and how it occurs. I also explained what happens, in detail, to each twin during pregnancy. I explained briefly about how it is detected and the newest treatment that has come out recently for Twin to Twin Transfusion Syndrome. I feel very confident with my work in this presentation and I have learned a lot about Twin to Twin Transfusion Syndrome and twins in general.

•“The Twin to Twin Transfusion Syndrome Foundation” Last Update September 25, 2002 <http://www.tttsfoundation.org/> (Accessed January 2 2003)

•“Facts about TTTS” <http://www.twinhope.com/facts.html> (Accessed January 4 2003)

•“Twin to Twin Transfusion Syndrome” <http://ttts.8k.com/what.htm> (Accessed January 7 2003)

•“Twin to Twin Transfusion Syndrome” <http://www.fetalmd.com/ttts.htm> (Accessed January 4 2003)

•“An examination of TTTS” <http://www.bellaonline.com/articles/art2997.abducted scapular plane> (Accessed January 13 2003)

•“Twin Transfusion Syndrome” <http://www.stjh.net/causes.asp> (Accessed December 20 2003)