What is TTTS?

TTTS stands for Twin to Twin Transfusion Syndrome which is a disease of the placenta affecting (and often killing) identical twins either during pregnancy or shortly after birth.

Identical twins are created from the same fertilised egg, whereas non-identical (or fraternal twins) are created by the fertilisation of two separate eggs ovulated during the same menstrual cycle. There are different types of identical twins, however, with one particular type exposed to the serious risk of TTTS.

The differences relate, in essence, to the “speed” at which, following fertilisation, the single fertilised egg divides into two embryos. When a fertilised egg “twins” within the first four days of conception, each identical twin will enjoy nutrition from its own placenta. Identical twins feeding from separate (or dichorionic) placentas are not at risk of TTTS. When the fertilised egg “twins” between 4 and 8 days, the identical twins will share the same (monochorionic) placenta, but generally the twins will still grow within individual sacs of amniotic water (diamnionic sacs). If the fertilised egg “twins” after 8 days from conception, as well as sharing a monochorionic placenta, they will also grow within the same (diamnionic) sac.

All monochorionic identical twins are at risk of illness through TTTS, but the biggest risk of all is for monochorionic and diamnionic (so shared placenta and shared sac) identical twins. Unfortunately, this group is the most common “identical twin” group, which means lots of anxiety and concern for most expectant parents of identical twins. Research shows that the disease affects nearly 10% of all identical twin pregnancies.

The cause of the disease

The monochorionic placenta is an extremely complex structure. Within the structure are blood vessels shared by mother and baby but there are also blood vessels which result in some shared (so “transfused”) blood circulation between the identical twins. These combinations of blood transfusions are at the root of TTTS, so at the heart of the medical research funded by the Wiseman Trust.

The symptoms of the disease

The transfusion of bloods from one twin (the donor) to its sibling twin (the recipient) result in the recipient becoming small and anaemic through a shortage of blood and the donor becoming bloated and jaundiced through its blood ‘dominance’. However, TTTS does not discriminate in its highly destructive path. Untreated, the disease is very often fatal for both the donor and the recipient, either during the pregnancy or shortly after birth.

The Wiseman Trust’s Mission

TTTS has been the cause of death for thousands of babies. It has been the cause of distress for thousands of parents.

The Wiseman Trust has now raised nearly £1,000,000 to fund medical research into the underlying cause and treatment of this killer disease.

The Wiseman Trust will not stop its fundraising until the underlying cause has been found and cured.