Twin – to – Twin Transfusion Syndrome

Twin – to – Twin Transfusion Syndrome (TTTS, Twin – Twin Transfusion Syndrome, Feto fetal Transfusion Syndrome or Fetal Transfusion Syndrome) occurs specifically with identical twins, sharing the same placenta (A temporary organ joining the mother and fetus. Contains rich supply of blood vessels. The placenta transfers oxygen and nutrients from the mother to the fetus, and removes carbon dioxide and waste products from the fetus. The full length of the placenta is about seven inches in diameter and less then two inches thick.) Normally or during healthy gestation period, the exchange of blood between the twin fetuses occurs so that one twin will receive and pumps blood to the recipient or other twin. However, in Twin – Twin Transfusion Syndrome, the blood will flow unevenly. One of the fetal twin’s will receive too much blood and the other will not get enough blood to provide sufficient nutrition. The recipient receives too much blood, may experience heart failure due to continual strain on its heart and blood vessels. The donor twin may experience life – threatening anemia (blood Disorder: The number of red blood cells becomes too low. This can cause fatigue, and stress on bodily organs. Insufficiently, carrying oxygen to the body tissues.) or inadequate supply of blood. Twin – Twin Transfusion is confirmed after birth (assuming both fetuses survive), by a blood cell count, which will show anemia in the donor and excess red blood cells in the recipient twin. This syndrome can occur any time during the pregnancy, including during delivery. Estimated to occur up to 15 percent of identical twin pregnancies, and develops in mid pregnancy from about 16 weeks to about 28 weeks. Available medical options treating Twin – to – Twin Transfusion Syndrome or suggestions for treatment, depending upon the severity of the situation. If Fetal Transfusion Syndrome is left untreated, there is a 70 – 100 percent chance that the twins will not survive, when detected in the first 20 weeks of pregnancy.

Fetal Transfusion Syndrome has many complications. The recipient twin (or donor) receives to much blood will urinate more and have excess amniotic fluid (A colorless liquid that surrounds and protects the baby inside the amniotic sac within the uterus. Prior to expected delivery time, the amniotic sac ruptures, sometimes referred to as “water breaking.”). This called polyhydramnios, can cause premature rupture of the membrane (“water breaking”) causing miscarriage or preterm delivery, and pressure on the umbilical cord. The mother appears larger than expected for the time of the pregnancy. Upon examination of ultrasound, the twin will appear to have an enlarged bladder. The donor twin (or other twin) has less ammonitic fluid or small amount of fluid (oligohydramnios). Also, more amniotic membranes surround the twin, and upon birth. Appearing on ultra sound to be stuck in place on the wall of the uterus. (“Stuck twin phenomenon”). Since there is not enough nutrients or not enough blood (or oxygenated blood) occurs intrauterine growth retardation. An ultrasound shows a fetus appears smaller than expected by the gestation age, and upon birth. Termination of the pregnancy maybe recommended (Induction of labor through vaginal delivery or surgical termination) before the 20 week of pregnancy, if the Fetal Transfusion Syndrome dangers the mother’s health, difficulty of treatment or possibility of damage to one or both fetuses already exist.

Medications maybe prescribed either orally or intravenously to modify the fetuses circulation, recipients amniotic fluid or preterm labor for treating Fetal Transfusion Syndrome. However, administering medication will cross the placenta and can have serious side effects both fetuses and mother.

Treatment options for Fetal Transfusion syndrome before birth, includes preterm delivery, Amnioreduction, laser coagulation, and amniotic septostomy. Preterm delivery is usually recommended if twin – twin transfusion syndrome occurs after 25 to 28 weeks. Amnioreduction is a procedure for milder presence of Fetal Transfusion Syndrome, removes excess amniotic fluid from the recipient twin (1 – 3 liters). This procedure offers many benefits: Decreases the risk of premature labor or “water breaking” prematurely, relieves pressure on the umbilical cord of the twin, and improves blood flow between the fetus and the placenta. This procedure will need to be repeated because fluid will accumulate again (Every few days or weeks). The survival of the recipient twin increases between 50 – 60 percent but the twin has 20 – 35 percent probability developing severe heart or brain abnormalities, and cerebral palsy. The risks involved for Amnioreduction can cause bleeding and infection. Laser coagulation is fetal type of surgery. Laser coagulation is done while the mother is placed under epidural or general anesthesia. Through the use of an endoscope, inserted into the uterus, the surgeon uses a laser fiber to coagulate (closes blood vessels through an electric current that produces heat) or block blood vessels that connect one twin to another. Those blood vessels that connect each fetus to its own side of the placenta are not coagulated. The survival of both twins: 30 – 40 percent and the survival of least one twin: Between 70 – 80 percent of pregnancies. Overall complications is less than ten percent, includes fewer cases of severe heart and brain damage. Laser coagulation surgery has great been improved by the use of magnetic resonance imaging (MRI), and computerized three-dimensional reconstruction, which helps provide the surgeon with pin – point accuracy. Amniotic septostomy surgical procedure involves, creating one or more holes between two amniotic cavities. This hopefully will allow fluid from the recipient twin to flow to the other or donor twin. Each twin would have normal amount of amniotic fluid. This type of fetal surgery does not change the amount of blood each of the fetuses receives. Also, increases the risk that once the membranes are disrupted, may lead to the death of the fetuses from cord entanglement. Amniotic Septostomy is less likely a procedure that would be recommended.

Announced in April 2006, The Food and Drug Administration approved Humanitarian Device Exemption (HDE) for treatment of the fetuses with twin – twin transfusion syndrome. Through the use of a fetoscope (telescopic camera used to view a fetus), sheaths (used to pass surgical instruments and fluid through an entry site), and use of laser, which coagulates blood vessels to normalize the flow of blood between the twins. This procedure is recommended for gestation age of the fetuses between 16 – 26 weeks.