by Twin-to-Twin Transfusion Syndrome is one of the extra health concerns that are unique to a twin pregnancy.
Twin-to-Twin Transfusion Syndrome, or TTTS, occurs only with identical twins while still in the womb. Only monochorionic twins, or those that share a placenta, are susceptible to TTTS. TTTS is a rare condition that happens in only 10-15 percent of identical twin pregnancies.
Due to how abnormal blood vessels form in a shared placenta, TTTS occurs when one twin becomes a “donor” and transfers blood to the other twin (known as the “recipient”). The donor twin will have stunted growth due to a lack of blood and amniotic fluid. The recipient twin will have too much blood and amniotic fluid and subsequent heart trouble.
Why does TTTS happen?
Why TTTS occurs is largely unknown, but it can occur during any point in the pregnancy and can happen suddenly. Moms often indicate that their belly seemed to grow significantly bigger overnight or they experience rapid weight gain (not due to eating).
Ultrasound Detection
Your doctor will be able to tell early via ultrasounds what types of twins you are expecting and if they share a placenta or not. Due to the complexities of twins pregnancies, Mom will be getting lots of ultrasounds. There will therefore be lots of opportunities to monitor and verify the health of your twins.
Prevention and Treatment
Some research indicates that TTTS can be prevented with certain nutritional plans. A TTTS diagnosis will likely mean bed rest for Mom. Laser surgery can be used in severe cases to prevent further transfer of blood between the twins.
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TTTS, like many health concerns with twins, is a very serious issue. It can lead to health issues with your twins and even death. However, the odds are in your favor that it won’t happen with your twins. When TTTS does occur, advances in modern medicine allow early diagnosis and highly successful treatment that will likely lead to two healthy babies joining your family.
Due to the wide variety of possible twin complications, I advise that you take the preventative measures you can, but don’t stress out about every possibility. As a new diagnosis or information becomes available during the twin pregnancy, consult with Mom’s doctor and take action accordingly.
For more information on Twin-to-Twin Transfusion Syndrome, visit the TTTS Foundation, which has a comprehensive explanation of the details of TTTS including a list of questions to ask your doctor.
Share Your TTTS Story
James Bethe’s twins were born super early due to TTTS. Listen or read about his family’s experience with TTTS on this episode of the Dad’s Guide to Twins Podcast.
Josh Wise and his wife discovered their twins had TTTS just 8 weeks after they found out they were pregnant with twins. Listen to or read his experience here.
Did your twins have TTTS? Share your experience in the comments below.
(RELATED: Still looking for the right twin gear? See my Twin Baby Gear Essentials.)
Picture by Anfuehrer
Thank you for writing about this. Our babies had this and they’re a couple of energetic almost 10 months old now because we had an amazing team of Doctors supporting us. But people need to know about this! My advice is DO NOT WAIT! Get those ultrasounds done, and if it happens, solve it quickly. Good luck!
@Yamila – Thanks for sharing your experience. It is a great example of how parents of twins can overcome the challenges of TTTS through early detection and great medical care.
It’s not true that nutritional plans lead to prevention. That’s a misnomer. It’s very important that mothers of identical twins get very good antenatal care, and are referred to hospitals with the right equipment to monitor the babies’ development.
Very good research into TTTS can be found here:https://www.tamba.org.uk/TTTS
@Irene – thanks for sharing that resource
My girls are survivors of this! This is the scariest thing to go through, but a great team of doctors can work miracles! I had laser ablation surgery at 20 weeks and over night my “donor” was up to low normal fluid levels. If you are not being monitored at least every 2 weeks for an identical twin pregnancy, switch doctors! ! Early detection is key!! My girls are 3 now!!
@Danielle – Great to hear your success story! Thanks for sharing your experience with us.
My boys had TTTS at 17 weeks. We had surgery at 18 weeks. My water broke at 28 and they were born at 30 weeks. It’s a long story hat I’m writing in detail for a book. My boys spent 39 days in NICU and now they are happy healthy 20 month olds!!! I want my story told so maybe others can learn and understand what this awful disease is and does. Prayers to all who’ve had to go through this or are going through this!
@Jessica – thanks for sharing your story. I look forward to seeing your book!