World SIUGR Awareness Day Date in the current year: December 9, 2024

Twin-to-twin transfusion syndrome (TTTS) is a complication of monochorionic twin pregnancy (i.e. when the twins share a single placenta) characterized by disproportionate blood supply between the fetuses. In addition to the classic form of TTTS, there are several variants of the syndrome: twin anemia polycythemia sequence (TAPS), selective intrauterine growth restriction (SIUGR or sIUGR), and twin reversed arterial perfusion sequence (TRAP sequence or TRAPS).

SIUGR is a monochorionic twin pregnancy complication where the growth of one twin is restricted due to unequal placental sharing. In SIUGR, the distribution of blood is more balanced than in classic TTTS, but one of the fetuses does not receive the amount of nutrients and oxygen it needs due to having a smaller share of the placenta. As a result, one of the twins thrives while the other grows poorly; the size mismatch between the twins is typically more than 20%.

SIUGR isn’t dangerous just for the growth-restricted twin. If the growth-restricted twin dies in utero, the other twin may lose a significant amount of blood through the blood vessels shared by the fetuses and develop anemia.

SIUGR causes no physical symptoms in the mother; it is usually diagnosed during an ultrasound examination. There are three types of SIUGR depending on the blood flow in the umbilical artery of the growth-restricted fetus. Type I is the least serious; it usually does not require treatment, only regular monitoring. Types II and III have a high risk of complications and may require laser surgery.

World SIUGR Awareness Day is one of four awareness days observed during World TTTS Awareness Month, alongside World TTTS Awareness Day, World TAPS Awareness Day and World TRAP Awareness Day, observed on December 7, 8, and 10, respectively. It was created by the The Twin to Twin Transfusion Syndrome Foundation (TTTS Foundation).

The TTTS Foundation was established by Mary Salman who lost one of her twins to TTTS in 1989 and took a pledge to make sure her babies would be known and remembered. Salman coined the term “daisy babies” for babies who have survived TTTS, established the TTTS Foundation, and created awareness days to raise awareness of TTTS and its forms.

The main goals of World SIUGR Day are to increase awareness of SIUGR among both healthcare professionals and the general public, encourage research into SIUGR, and provide help and support to families affected by the syndrome. You can join the campaign and shine a light on SIUGR by posting on social media with the hashtags #WorldSIUGRDay and #WorldSIUGRAwarenessDay.

World SIUGR Awareness Day should not be confused with Intrauterine Growth Restriction Awareness Day (IUGR Awareness Day), observed on March 13. IUGR can occur in singleton pregnancies, whereas SIUGR is a form of intrauterine growth restriction that occurs specifically in twin pregnancies.