Twin to Twin Transfusion Syndrome (TTTS) is a rare complication that can affect twins who share both a placenta and some of the same circulation allowing blood to pass from one twin (the donor) to the other (the recipient).
The donor twin may become smaller and anaemic due to a lack of blood supply.
The recipient twin has a higher blood volume, which can strain the foetus’ heart and lead to heart failure.
The donor twin is also likely to have a decreased urinary output, leading to a lower than normal level of amniotic fluid, whereas the reverse is true for the recipient twin.
The excess fluid in the recipient twin is called polyhydramnios and can lead to discomfort for the pregnant mother. Pressure on the cervix can lead to ruptured membranes and early delivery.
When you have your first ultrasound scan, the sonographer will be looking for signs that your twins are monochorionic (ie they share one chorionic sac). If so, your pregnancy will be carefully monitored for signs of TTTS.
If there is a problem as your pregnancy progresses, you may ultimately be referred to a specialist centre for laser ablation therapy, which separates the blood vessels in the placenta.
Visit the Twin to Twin Transfusion Syndrome Foundation’s website for more information.
tamba.org.uk is a great information source for mulitple pregnancies. Visit their website to download their free booklet The Healthy Multiple Pregnancy Guide.