With a one and a half year-old, my husband and I made the ever-so-familiar trek to Seattle to visit my sister who had recently discovered she was pregnant. Jodie was a handful at the time, magnetically attracted to all things made of glass or porcelain: pictures, vases, trinkets, tea sets, and china. As we entered my sister's house, we felt a sense of impending doom: Jodie was off to the races and my sister and her husband were actually sitting in the living room in silence, with half-smiles reluctantly pasted on their faces. Dear God, they were already irritated with the presence of a toddler, how would they manage on their own in this quasi-museum of a house? All Hell broke loose as Jodie gathered each every breakable object within arms length. Again, they were silent, speechless. I figured this shock-and-awe emated from my daughter's antics and the ensuing petrification upon realizing they'd have their own permanent, glass-hoarding resident.

A negligible, piece of paper was gently sewn between my sister's fingers, slight but heavily significant. “Look!” she exclaimed. “What do you see?” Have you ever seen a fetal ultrasound picture? There are nonexistent entities there: swirls and whirls of life there to trick the observant eye. “UH, LIFE, sis, Life.” “No, no, look again...” Okay, there was a definite circular pattern of matter, with an adjacent hazy conglomeration of streaks and dots. “Uh, Laura, don't you see something else there?” Oh, Dear God, tell me it's not:”TWINS.” “There are twins in here!” Gulp. Oh, no, no, no. Stress does not become this sister of mine. I am the one who can handle twins. She and my brother-in-law looked simply aghast, like I was the one to take away all their pain. Crumpling up the picture, embracing the sweet sorrow, I moved toward them ready for a sweet embrace when I was suddenly interrupted by: “April Fool's!”

Oh, dear God, how have I fallen for such a ghastly trick, I thought, as I yanked a variety of fragile artwork from the claws of my toddler. As I returned the pieces to their proper place, they were still laughing, and my sister made her way to the kitchen for another vitamin shake.

They soon became the victims of their own April fool's joke. Just weeks later at the next ultrasound it was confirmed that she was indeed pregnant with twins. Little did we know it was no laughing matter, what started out as celebratory turned quite dire.

Twin to Twin Transfusion Syndrome (TTTS) can only happen in pregnancies with identical twins. They must have a monochorionic placenta: they share a placenta, but have separate water bags (diamniotic). Since this only happens with identical twinning (monozygotes come from the same egg) the fetuses will be the same gender. TTTS occurs when the fetuses share circulation, i.e. blood vessels. Consequently, there is a discordance of blood flow whereby one twin gets a disproportionate amount of blood flow (called the recipient) and the other twin gets too little (called the donor). This results in the donor twin being "shrink wrapped" in the membrane and the recipient receiving an excess of blood and becomes overloaded. The donor twin is often the smaller twin and can suffer from anemia due to inadequate blood supply. This twin will try to compensate for the lack of blood supply by shutting down critical organs, in particular the kidneys, resulting in a small amniotic sac from reduced urine output. Conversely, the recipient twin is generally the bigger of the two and will produce large amounts of urine to compensate and will have an abnormally large amniotic sac. The recipient twin can show signs of cardiovascular failure from attempting to pump out the excess of blood. The heart may become thick and enlarged.

The first two weeks of pregnancy is the time when the type of placenta is determined by the twinning process.  If twinning occurs within the first four days, they will have separate placentas, called dichorionic.  After four days, they will be monochorionic, that is, they will have a shared placents with separate amniotic sacs (diamniotic).  After day eight, the twins will be monoamniotic:  they will share both the same placenta and water sac.  Finally, after twelve days, the rare occurence of Conjoined Twins (Siamese Twins) will result. Thankfully, my nephews were monochorionic, since monoamniotic pregnancies carry all new risks, such as cord entaglement.  It's always strang to think that they were just days away from being conjoined...

Ultrasound can detect the presence of TTTS with the following criteria:

1. The twins must be monochorionic (share the same placenta) and the same gender.
2. A size discrepancy will exist between the two fetuses.
3. One twin will have an excess of amniotic fluid (the recipient's polyhydramnios) while the other will have a shortage (the donor's oligohydramnios).

Other common findings that are indicative of TTTS and aid in diagnosis:

• The bladder of the donor twin will be small or unable to visualize
• The recipient's bladder will be enlarged
• Growth disconcordance between the two twins
• Differences in umbilical size between the twins
• Cardiac distress signs in the recipient twin (much less often in the donor)
• Abnormal umbilical cord insertion and differences in umbilical cord doppler readings

1. Unusual weight gain.  Sometimes the abdomen will appear lopsided where the recipient has a surplus of amniotic fluid.
2. Unusual body swelling
3. Early contractions
4. Possibly bleeding

 It can happen at any time during the pregnancy, however it is most commonly diagnosed between weeks 15 to 20.

Dr. Quintero et al has proposed 5 stages of TTTS from ultrasonography findings. They are progressive, meaning each stage indicates more advancement of the TTTS.

1. There is excess amniotic fluid in the recipient and a shortage of amniotic fluid in the donor. However, the donor's bladder is still visible on ultrasound.
2. The amniotic fluid discordance continues, but the donor's bladder becomes invisible on ultrasound.
3. In addition to the above 2 stages, the blood flow in the umbilical cords is abnormal as measured by doppler.
4. Hydrops (an accumulation of fluid that indicates heart failure) is seen in either twin. Again, this is usually seen in the recipient twin. Normally laser surgery (called laser photocoagulation) is recommended here. (Discussed in treatment options below)
5. One or both babies have died.

Sadly, the prognosis is quite bleak. In fact, the earlier the syndrome appears, the worse the prognosis. Fortunately, it is a rare syndrome and occurs in only 5% to 10% of all monochorionic twin pregnancies. This encompasses an occurence of 0.1 to 0.9% per 1000 births.

Dr. Quintero is a world-renowned fetal surgeon and pioneer of the surgical technique for identifying and lasering specific blood vessels that are the culprits in TTTS. He is also the developer of the five stages of twin to twin transfusion syndrome that is used worldwide. He's a Professor at University of South Florida as well as the Director of Maternal Fetal Medicine in Obstetrics and Gynecology.

There are 5 primary treatment options for TTTS:

1. Therapeutic Reduction Amniocentesis (sometimes called Amnioreduction): This is generally the starting point after diagnosis and the most widely used treatment. This is where my sister started. The procedure resembles amniocentesis in that a needle is inserted into the amniotic sac of the recipient and excess fluid is drained. The desired outcome is that this procedure will aid in stabilizing the disproportionate fluid surrounding each twin. Unfortunately, it's not just done once, it will need to be a regular procedure during the TTTS pregnancy.
2. Amniotic Septostomy: During ultrasound, a needle is inserted into the mother's abdomen and the membrane between the recipient and donor is punctured slightly to attempt to establish equilibrium between the two sacs.
3. Umbilical Cord Ligation: A sad option when one of the twins is near death and threatening to destroy the chances the other twin's survival. This is basically selective reduction. This is done after every attempt has been made to save both fetuses, but with no success. A knot is tied around the cord of one of the twins to stop its heart from beating.
4. Fetoscopic Placental Laser Therapy (also called Laser Photocoagulation): Pioneered by Dr. Ruben Quintero, this treatment offers the most hope by actually fixing the undesireable connecting blood vessels. A tiny telescope is inserted into the uterus whereby doctors are able to see the offending blood vessels/connections. They are then able to destroy all these connecting vessels with a laser.
5. Medication Therapy:

• Digoxin- This is either given to the mother or it's injected into the twin suffering from symptoms of heart failure.
• Indomethacin- This can decrease amniotic fluid production and help stabilize the amniotic fluid volume in each twin. It's commonly given to women to stop preterm labor and has disappointing result in treating TTTS.
• Tocolytic Medications: Like Indomethacin, these help stop preterm labor (a common threat in a TTTS pregnancy).

When my sister made it to stage 4, things were extremely dire, her recipient was in heart failure. Her perinatologist offered very little hope, she said she should consider abortion at this point. Fortunately, they didn't give up and got in touch with the Twin To Twin Transfusion Syndrome
Foundation (http://www.tttsfoundation.org/) where they learned about Dr. Quintero's surgery. This was in 2001 and he was the ONLY doctor in the country offering the laser surgery. They quickly called Dr. Quintero and discovered he was unavailable to perform the surgery for another week.

Her twins couldn't wait a week... From the TTTS foundation, they found out about the only other surgeon in the world offering the laser surgery. The good news? The surgery could be performed right away. The bad news? He was located in London, England and they live in Seattle, WA. His name is: Dr. Kypros Nicholaides. He's at The Harris Birthright Research Centre at Kings College School of Medicine. As quickly as they could get their plane tickets, they were on their way around the world. The plane ride was excruciating, her abdomen was overflowing with amniotic fluid, especially on one side. Here were the odds as he presented them back to her in 1991 (they're different now): there was a 50/50 chance both babies would die, there was a 50/50 chance one baby would die and one would live, there was a 50/50 chance both would live. Thankfully, their's was a success story: both boys lived and are happy, healthy kids today. The "donor" twin does, however, have mild (barely discernible) cerebral palsy today probably from in-utero trauma.

 The Twin to Twin Transfusion Foundation has an excellent list of TTTS treatment centers.  They keep abreast of current information.  For a complete list, please visit:  http://www.tttsfoundation.org/laser_centers.php