National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Twin to twin transfusion syndrome


Other Names:
TTTS; Twin-to-twin transfusion syndrome; Fetofetal transfusion syndrome; TTTS; Twin-to-twin transfusion syndrome; Fetofetal transfusion syndrome; Fetal transfusion syndrome See More
Categories:
Twin to twin transfusion syndrome (TTTS) is a rare condition that occurs during a twin pregnancy when blood moves from one twin (the “donor twin”) to the other (the “recipient twin”) while in the womb.[1] TTTS is a complication that specifically occurs in identical (monozygotic) twin pregnancies that share the same "egg" sac (monochorionic) that may or may not share the same amniotic sac (monoamniotic).[2] TTTS usually develops between 15 and 26 weeks of pregnancy.[3] The donor twin may be born smaller, with paleness, anemia, and dehydration. The recipient twin may be born larger, with redness, too much blood, and increased blood pressure, resulting in an increased risk for heart failure. Treatment may require repeated amniocentesis during pregnancy. Fetal laser surgery may be done to interrupt the flow of blood from one twin to the other. After birth, treatment depends on the infant's specific symptoms. The donor twin may need a blood transfusion to treat anemia. The recipient twin may need to have the volume of body fluid reduced. This may involve an exchange transfusion. Medications may be given to treat heart failure in the recipient twin.[1]
Last updated: 7/21/2016

If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.

If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.

You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.

Healthcare Resources

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

  • ClinicalTrials.gov lists trials that are related to Twin to twin transfusion syndrome. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies.

    Please note: Studies listed on the ClinicalTrials.gov website are listed for informational purposes only; being listed does not reflect an endorsement by GARD or the NIH. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

  • MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.
  • The Twin to Twin Transfusion Syndrome Foundation has an information page that lists their most commonly asked questions regarding TTTS. Click on the link above to view this information page.

In-Depth Information

  • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Twin to twin transfusion syndrome. Click on the link to view a sample search on this topic.

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  1. Twin-to-Twin Transfusion Syndrome. MedlinePlus. 9/26/2015; http://www.nlm.nih.gov/medlineplus/ency/article/001595.htm.
  2. Terence Zach. Twin-to-Twin Transfusion Syndrome. Medscape. Dec 30, 2015; http://emedicine.medscape.com/article/271752-overview.
  3. Twin to twin transfusion syndrome. Orphanet. February 2012; http://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=en&Expert=95431.