The National Institute for Health and Clinical Excellence (NICE) issued full guidance to the NHS in England, Wales, Scotland and Northern Ireland on septostomy with or without amnioreduction for the treatment of twin-to-twin transfusion syndrome in December 2006. In accordance with the Interventional Procedures Programme Process Guide, guidance on procedures with special arrangements are reviewed 3 years after publication and the procedure is reassessed if important new evidence is available.

The guidance was considered for reassessment in December 2009 and it was concluded that NICE will not be updating this guidance at this stage. However, if you believe there is new evidence which should warrant a review of our guidance, please contact us via the email address below.


Twin-to-twin transfusion syndrome occurs when unborn identical twins have different sacs in the womb but share the same placenta. This results in blood flow from one twin to the other through connections between blood vessels in the shared placenta becoming unbalanced. The volume of fluid around the twins also becomes uneven. In septostomy with or without amnioreduction, a needle is used to make a hole in the membrane separating the twins to even out the volume of the fluid surrounding the babies. Sometimes excess amniotic fluid may need to be removed with another needle (this procedure is called amnioreduction).

Coding recommendations

R08.8 Other specified therapeutic percutaneous operations for twin to twin transfusion syndrome
Y33.8 Other specified puncture of organ NOC
Y53.2 Approach to organ under ultrasonic control
Y95.- Gestational age

Note:  A code from category Y95.- Gestational age must be assigned in a subsidiary position where this information is available.