Twin to Twin Transfusion Syndrome (TTTS)

Diagnosis of TTTS is based on the combination of several findings:

TTTS Assessment | Information you may find about TTTS | Do I have TTTS? | TTTS Diagnosis

You must have identical twins with a single placenta (monochorionic). This is most reliably seen by ultrasound in early pregnancy (before 16 weeks). After this time, a monochorionic pregnancy is likely if:
- There is a single placenta.
- Both babies are the same sex.
- The dividing membrane is thin all the way to where it meets the placenta.
There is a significant difference in their sizes.
There is a significant difference in the amniotic fluid volume in each sac.
There is marked difference in bladder filling between babies.
You are uncomfortable because your abdomen has suddenly become much bigger.
Your uterine contractions are worse since your abdomen has become bigger.

Patients who develop TTTS typically report some or all of these findings. If you are concerned about this possibility, you should contact your obstetrician or perinatologist.

This page was last updated on: October 3, 2007.

For detailed assessment, call the Center for Advanced Fetal Care at
1-888-349-8946 (FIX-TWIN).