Sometimes, clinically he althy mothers give birth to children with morphological defects: the absence of phalanges of fingers, limbs and even the head. Mothers come to despair, reproach themselves or doctors for what happened to their child. Sometimes it comes down to litigation. But what actually causes these birth defects?
Definition
Amniotic bands, otherwise called "amniotic adhesions" or "Simonard's bands", are a duplication of amnion tissue that is stretched between the walls of the uterus. As a rule, it does not harm the embryo and does not present complications in childbirth. But in rare cases, serious consequences are possible.
Amniotic bands are fibrous threads that originate in the amniotic sac. They can compress or bandage the umbilical cord, attach to parts of the body of the fetus, causing malformations (amputation of arms, legs, fingers or their phalanges, sometimes decapitation).
Reasons
There are two theories whyamniotic constrictions appear. The reasons for this phenomenon are explained by frequent ruptures of the amniotic bladder in early pregnancy. Since the chorion remains intact, there is no threat of interruption in the development of the embryo, but the threads that arise due to ruptures float freely in the amniotic fluid. They can cling to parts of the body of the fetus. With the course of pregnancy, the child grows, but the threads remain the same as they were, so there is tissue compression, ischemia and necrosis.
Some time later, a second theory appeared, as the first did not suit the skeptics, who noticed that amniotic bands (fibrous filaments in the abdomen of a pregnant woman) appear simultaneously with other congenital malformations, such as a cleft lip or a cleft palate. These doctors speculated that the bands were due to vascular or fetal circulatory disorders.
Another option for the development of events is an intrauterine infection, as well as trauma during pregnancy, anomalies of the genital organs (doubling of the uterus, bicornuate uterus, etc.), CSI (isthmic-cervical insufficiency), inflammation of the amnion, endometritis, oligohydramnios. But none of these theories have been conclusively confirmed.
Diagnosis
In most cases, clinically and laboratory findings fail to detect amniotic constrictions. The photo from the ultrasound study is not informative, since these threads are very thin. Indirectly, you can determine the enlarged and swollen limbs in places of compression. Widespread to a large extentoverdiagnosis of this pathology. Therefore, if the doctor suspects the presence of amniotic cords, the pregnant woman is referred for an MRI or 3D ultrasound.
More than half of the diagnosed amniotic constrictions on repeated ultrasounds are not detected due to their rupture.
Statistics
Depending on the technical equipment of the antenatal clinic, the frequency with which amniotic constrictions are detected can range from 1:1200 to 1:15,000 births. It is believed that two hundred out of ten thousand miscarriages occur for this reason. In eighty percent of cases, Simonard's bands deform the fingers and hands, and another ten percent is compression of the umbilical cord. It is the formation of knots on the umbilical cord that leads to hypoxia and antenatal death of the fetus.
Fortunately, most diagnoses of "amniotic band syndrome" are not clinically confirmed, or the fibrous sutures do not cause significant damage to the fetus.
Heredity
The likelihood that amniotic bands will appear during pregnancy is extremely small. This is not a hereditary disease. As a rule, genomic or chromosomal mutations appear symmetrically, but in this case, the threads are attached absolutely randomly. If during the first pregnancy the child had Simonard strands, this does not mean that subsequent children will have injuries. Also, this does not mean that a child with malformations will be born from parents who have suffered amniotic constriction syndrome in utero.
Consequences
Although amniotic constriction is not a fatal pathology, its consequences can be very depressing. Due to the fact that strands can entangle parts of the body of the fetus, lymph stagnation develops. This leads to edema and necrosis. After birth, such limbs must be amputated, otherwise CRUSH syndrome will develop: toxins that have accumulated in the anesthetized part of the limb will enter the systemic circulation and begin to poison the baby's organs. This could lead to his death. Therefore, it is necessary to remove the limb if it is no longer viable. And as soon as possible.
In addition, with the syndrome of amniotic constriction, depression of the limbs and fingers into the proximal part of the limb is possible. It is not uncommon among these children to have fusions of the fingers or phalanges of the fingers and toes. Sometimes, in addition to constrictions, a child has other stigmas of disembryogenesis: clefts of the hard palate and upper lip. In very rare cases, there are gross violations of the development of the spine and facial skull, eventration of the abdominal organs, umbilical cord atresia.
If the constriction affects the vessels close to the skin, then a hemangioma is formed at this place. The tumor will need to be removed after birth.
Some scientists find a link between Simonard bands and clubfoot. This is due to the fact that the legs of the fetus are fixed with fibrous threads, so the walls of the uterus can squeeze the feet of the fetus. In twenty percent of cases, this pathology is bilateral. Another risk that an obstetrician-gynecologist must consider is premature birth. Givencomplication is a common occurrence in pregnancies with amniotic constriction syndrome.
Treatment
As a rule, this disease is not treated in utero. In medical practice, there are casuistic cases when transvaginal or laparoscopic operations were performed. But this was an extreme measure, as vital organs were squeezed. But these are extremely rare amniotic constrictions. Treatment is usually given after the baby is born.
The fibers are dissected and, if necessary, part of the limb is amputated. To improve the quality of life, you can transplant fingers from feet to hands.
Forecast
Prognosis for life and he alth is usually favorable. Children in most cases grow and develop according to age. Every year, limb prostheses are improved, so if you lose a forearm, hand, lower leg or foot, it is possible to put an artificial replacement. Children are encouraged to change their dentures as they grow older. If the constriction caused a slight functional defect, then the cosmetic defect can be eliminated by transplanting the fingers, as well as their phalanges.
People with amniotic constriction syndrome can have completely he althy children, as this disease is not inherited.
Celebrities who had Simonard bands
Gone are the days when amputees hid in their homes and were ostracized by society. Nowthey can live with virtually no restrictions, hold important public positions, play sports, appear on television and participate in beauty contests.
Some famous people are not shy about being born with congenital amputations, but whether this was due to amniotic constrictions is an open question.
- Carrie Burnell is an actress who was born without her right forearm. She works on a children's TV channel. This caused a mixed reaction among young viewers and their parents and served as an impetus for the emergence of a series of programs on how to teach children about disabilities and the peculiarities of life of such people.
- Jim Abbott is familiar to all baseball fans. He is a legendary pitcher, that is, a pitcher, without a right hand. He retired from big sport at the end of the twentieth century, but his example continues to inspire many people with disabilities and Paralympians.
- Teresa Yukatil - the beauty of Miss America, was born without a left hand. During competitions, she did not wear a prosthesis to show that it is possible to be beautiful without artificial details.
- Kelly Knox is a top model without a left forearm. In 2008, she became the winner of a reality show on BBC 3. In addition to her, seven other girls with various injuries participated in this competition.
- Nicholas McCarthy is a famous pianist who was born without a right hand.
- Nikolas Vujicic is an Australian Christian preacher. Known for being born without all limbs. He publishes his books and travels with seminars around the world as an example of the fact that you should not give up even in the most difficultsituations.
- Mark Goffeny is a guitarist born with amputated arms. He learned to play with his toes.
