Causes of Polyhydramnios

Polyhydramnios is the condition that occurs when there is too much amniotic fluid surrounding a baby in utero. It has been associated with many conditions including brain and facial abnormalities, gastrointestinal obstructions, compressive pulmonary disorders, narrow thoracic cage disorders, neuromuscular impairments, maternal conditions, fetal anemia, blood incompatibilities, infections, fetal and placental tumors, fetal syndromes, and complications involving multiples.

Even though researchers have been able to link many different things with Polyhydramnios, as many as 60% of cases of Polyhydramnios are considered idiopathic at the time of delivery, meaning either it happened spontaneously or that the cause is not yet known. Up to 1/3 of those idiopathic cases end up being diagnosed with a genetic anomaly before the baby’s first birthday. 

This page contains a very extensive list of conditions that have been linked to Polyhydramnios. They are listed in alphabetical order.

Table of Contents


What causes amniotic fluid to build up?

Normally, while in the womb, babies swallow amniotic fluid, and then pee it back out. This is the natural process that keeps amniotic fluid at a steady level. But sometimes there is an interruption in this pattern leading to a build-up of amniotic fluid.

This occurs when:

  • baby’s ability to swallow becomes impaired
  • a certain condition causes excessive urination
  • there is an issue with the placenta, or
  • the baby has a congenital heart condition 

These problems are often caused by a congenital disability, a maternal condition, or a random anomaly. But there are also cases where women experience high levels of amniotic fluid for no apparent reason at all.


What is the most common cause of Polyhydramnios?

At the time of delivery, the majority of cases of Polyhydramnios are considered idiopathic. Past research identified Gestational Diabetes as the most common cause of Polyhydramnios, but new research has shown that the rate of cases caused by maternal diabetes is significantly less than previously thought. The most common *known cause of Polyhydramnios is  genetic anomaly, followed by infection, blood incompatibility, fetal anemia, complications of multiples, and gestational diabetes.  

  • 61% – idiopathic, (unknown)
  • 18% – genetic anomaly
  • 10% – other conditions (infection, blood incompatibility, placental problems, heart conditions, etc…)
  • 4% – fetal anemia 
  • 4% – complications of multiple pregnancy
  • 3% – maternal diabetes
Of that 61% of idiopathic cases, up to 1/3 of those babies will be diagnosed with a genetic anomaly before their first birthday. Those numbers are not factored into this data.

Conditions Linked to Polyhydramnios

ABO Incompatibility

ABO Incompatibility happens when mom and baby have different blood types and the missing protein in mom’s blood develops antibodies to that particular protein and attacks baby’s red blood cells . It is similar to Rh incompatibility. ABO incompatibility most often occurs when mom has type O blood (no proteins present) and her baby has A (A proteins), B (B proteins), or AB (both A and B proteins). It can very rarely occur in a mom who has type A (A proteins) with a baby who has B (B proteins) or AB (both A and B proteins), or in a mom who has type B (B proteins) with a baby who has A (A proteins) or AB (both A and B proteins). It NEVER happens when a baby has type O blood, since there are no proteins present in type O.

There is no prenatal test to detect ABO incompatibility. Babies born with ABO incompatibility usually have elevated bilirubin levels and sometimes have symptoms of anemia. Treatment includes light therapy and very rarely, blood transfusions to replenish damaged red blood cells.

Signs: jaundice, and sometimes anemia. 


Anencephaly is a neural tube disorder in which a large part of the brain, skull, and scalp are missing. This condition is very rare, affecting 0.3% of babies. Babies born with this condition will be unconscious and usually survive from only  a few hours, up to one week. There is no medical intervention for anencephaly and the goal is to make the infant as comfortable as possible. Anencephaly is easily diagnosed by routine ultrasound.

Signs: part of the skull appears missing and brain tissue may be seen on ultrasound, a smaller than expected crown to rump length.

Antenatal Bartter Syndrome


Antenatal Bartter Syndrome – is actually a group of related genetic disorders that affect the kidneys and cause a dangerous electrolyte imbalance in babies. Antenatal Bartter Syndrome can be suspected prenatally when there is early onset of severe Polyhydramnios without obvious genetic abnormalities, excessive urine output in the fetus, and elevated levels of chloride and aldosterone are detected in amniotic fluid. Molecular genetic testing after birth can confirm the diagnosis. With Antenatal Bartter Syndrome, AFI usually rises to very severe levels requiring multiple amnioreductions. Treatment for most types of Antenatal Bartter Syndrome is lifelong and involves managing the symptoms and keeping the body’s electrolytes in balance. This is usually done by a combination of medication and supplements.

One type of Bartter Syndrome, Transient Antenatal Bartter Syndrome, goes away shortly after birth, but it can cause major complications for the newborn if it is not caught. This 2018 study was done to analyze the proportion of the population with a specific gene mutation that has been detected in some cases of Transient Antenatal Bartter Syndrome and idiopathic polyhydramnios.

Signs: fetal polyuria (large amounts of urine), early onset of Polyhydramnios, fetal growth restriction, preterm birth, postnatal polyuria, episodes of dehydration, recurrent vomiting, and failure to thrive.

Beckwith-Wiedemann Spectrum Disorder


Beckwith-Wiedemann Spectrum Disorder – is an overgrowth disorder that can affect one part, multiple parts, or just one side of the body. Children with Beckwith-Wiedemann are at an increased risk of developing certain types of cancers, especially of the liver and kidneys. However, most children with BWS grow up to live normal adult lives. There are specific clinical criteria used to suspect BWS, and a methylation test will be positive in up to 80% of cases. Treatment for children with Beckwith-Wiedemann’s is preventative, monitoring to watch for the development of tumors including bi-monthly abdominal ultrasounds and AFP blood tests.

Signs: creases or pits on the ears, macroglossia, omphalocele, umbilical hernia, larger than normal abdominal organs, macrosomia, cleft palate, hypoglycemia, polyhydramnios, diastasis recti in baby, port wine stains, and hemangiomas.

Cantu Syndrome

Cantu Syndrome is an extremely rare condition affecting genes on the 12th chromosome, primarily in the ABCC9 gene. Cantu Syndrome is considered a spectrum disorder that is most commonly characterized by excess hair growth, certain heart defects (a large heart or patent ductus arteriosus), and macrosomia. However, it can present with a wide range of other features such as low muscle tone, distinctive facial features, increased susceptibility to respiratory infections, lymphedema, scoliosis, and mild developmental delays. Medical literature varies, but to our understanding, Cantu Syndrome has only been identified in fewer than 150 individuals. However, some literature we looked at suggested that many more people are actually affected.  

Signs in newborn: polyhydramnios during pregnancy, macrosomia, generalized edema after delivery, and hypertrichosis with thick scalp hair and excessive hair growth on the forehead, face, back, and extremities.  


Chorioamnionitis is a bacterial infection of the amniotic fluid, usually caused by an infection that has spread from the maternal urinary tract. It occurs in roughly 2% of all pregnancies and is a cause of premature birth. If your doctor suspects an infection, blood tests may help confirm it, and an ultrasound can help check on the health of the baby. Sometimes you may be treated with antibiotics, but usually, a quick delivery is preferred. Complications of chorioamnionitis include infections of the pelvis, abdomen, lining of the uterus, or of the blood (sepsis), or dangerous blood clots in the pelvis and lungs.

Signs in mother: fever, rapid heartbeat, tender uterus, or foul-smelling discharge.

Congenital Diaphragmatic Hernia

Congenital Diaphragmatic Hernia – is when there is a hole in the diaphragm that allows abdominal organs to slip through into the chest cavity resulting in compression of the lungs. This causes underdeveloped lungs and can lead to pulmonary hypoplasia. CDH can be detected by routine ultrasound, and if it is seen, further testing is required to determine the cause. Fetoscopic Tracheal Occlusion is a procedure that is often used to treat CDH in utero to help the lungs grow. Early delivery may also be needed depending on fetal well-being. Surgery shortly after birth will repair the diaphragm but artificial ventilation may still be needed to help underdeveloped lungs.

Signs: chest movements that don’t coordinate with baby’s breathing rhythm, absent breath sounds on the affected side, bowel sounds heard in the chest, concave abdomen that feels less full when touched.

Congenital Pulmonary Airway Malformation (CPAM)

Congenital Pulmonary Airway Malformation (CPAM) is a very rare condition where a lesion forms on a baby’s lung in utero. CPAM can range from mild to severe, with the most severe cases causing fetal hydrops and mirror syndrome in the mother. Fetal CPAM is often detected by ultrasound and confirmed by MRI and fetal echocardiogram tests. Regular monitoring is required to see how the lesions are growing and if hydrops is developing. Treatment depends on the severity of the case and include steroid treatment, thoracentesis, fetal surgery, or early delivery. Newborns with CPAM may be born via EXIT where they undergo surgery while still attached to the placenta, have surgery shortly after birth, or have surgery scheduled for up to a year later to remove the lesions so they do not become infected.

Signs: respiratory distress including grunting, rapid breathing, and oxygen requirement, recurrent infections, coughing up blood, shortness of breath, chest pain, coughing, fever, and failure to thrive.

Congenital Myopathies

Congenital Myopathies a group of rare muscle diseases caused by genetic defects that usually involve low muscle tone and weakness. Congenital myopathies are usually present at birth, but signs may not be noticed until later in infancy or even into early childhood. Testing for congenital myopathies after birth may include blood tests, electromyography, genetic testing, or a muscle biopsy. If a known family history of myopathies exists, genetic testing may be done prenatally. There is no cure for genetic myopathies but there are many supportive treatments available to help manage symptoms.

Signs: lack of muscle tone, muscle weakness, delayed motor skills, noticeable facial weakness, muscle cramps, or contractions.

Congenital Myotonic Dystrophy

Congenital Myotonic Dystrophy – a type of myotonic dystrophy that causes progressive muscle weakness and breakdown. The signs of congenital myotonic dystrophy may present at birth, or later into childhood. Congenital Myotonic Dystrophy is an inherited disorder and only shows up in babies born to a mother who also has Myotonic Dystrophy. There is no cure for Congenital Myotonic Dystrophy, but the management of symptoms, education, and occupational therapy have all proven to be helpful with this disorder.

Signs: weak muscle tone, breathing problems, club feet, developmental delays, and intellectual disabilities.

Dandy-Walker Syndrome

Dandy-Walker Syndrome – a congenital brain defect that can cause slow motor development and enlargement of the skull due to hydrocephalus. The prognosis of babies with Dandy-Walker Syndrome is highly variable, ranging from mild to life-threatening, and depends largely on how the associated symptoms are handled. Dandy-Walker Syndrome can sometimes be detected during a second-trimester ultrasound. 80% of cases are detected within the first year of life, usually due to the symptoms of the related hydrocephalus. Treatment is dependent on each individual case.

Signs: developmental delay, low muscle tone or later high tone (spasticity), poor coordination or balance, and sometimes a large head circumference and pressure inside the skull. Mental retardation and seizures may be present when hydrocephalus is severe.

DiGeorge Syndrome

DiGeorge Syndrome (22q11.2 deletion syndrome) – is a genetic disorder that happens when part of chromosome 22 is missing. The symptoms of DiGeorge can sometimes be seen at birth, but may not become apparent until later in childhood. A blood test designed to detect chromosome 22 can be done to confirm suspicions of DiGeorge Syndrome. Treatment involves managing the symptoms of each specific case and may include surgeries for heart conditions or physical malformations, treatment of infections, mental or behavioral therapies, and occupational, speech, and physical therapies. 

Signs: heart defects, a poor immune system, cleft palate, problems from low calcium levels, and delayed developmental and behavioral development. 

Duodenal Atresia

Duodenal Atresia– is a condition in which there is a blockage between the stomach and the upper part of the small intestine resulting in liquid not being able to leave the stomach. DA is usually diagnosed in the second half of pregnancy when there is reason to believe it may be present, like red flags from genetic testing or the presence of Polyhydramnios. An ultrasound can usually detect DA by the presence of a “double bubble”, which is when fluid can be seen in the stomach and the upper part of the duodenum, but nowhere else in the GI tract. DA is not treatable during pregnancy, but it can be surgically corrected after birth. *Approximately 1 in 3 babies born with DA also have Down Syndrome.

Signs: upper abdominal swelling, early vomiting of large amounts (which may be green), continued vomiting even after not feeding for several hours, no bowel movements after the first few meconium.

Esophageal Atresia

Esophageal Atresia – is a condition in which there is a blockage between the esophagus and the stomach. The esophagus is the tube that connects the back of the throat to the stomach. Esophageal Atresia can be a partial blockage, or it can present as a complete disconnection. There is no prenatal treatment for EA, but this condition will require surgery shortly after the baby is born and an extended NICU stay until the baby is able to eat without support.

Signs: frothy white bubbles in mouth, coughing or choking while feeding, vomiting, blue color of the skin especially when feeding, difficulty breathing, and a very round, full abdomen.

Fetal Anemia

Fetal Anemia in a baby can cause jaundice, kernicterus, fetal hydrops, heart failure, and respiratory problems. Treatment in utero may require a fetal blood transfusion or early delivery. Treatment after delivery may include aggressive hydration, phototherapy, blood transfusions, and treatments for heart failure. Fetal anemia is usually caused by Rh incompatibility or infection. It can be detected by ultrasound if there are signs of heart failure or hydrops, or if there is increased blood flow in the middle cerebral artery.

Signs: fetal heart failure or hydrops detected on ultrasound, certain antibodies in mother’s blood that cause anemia, reduced blood flow through the middle cerebral artery, and jaundice after birth.

Fetal Bowel Obstruction

Fetal Bowel Obstruction – the bowels are made up of the small intestine and large intestine. A bowel obstruction is usually caused by atresia, or narrowing, somewhere in the small intestine, but not always. Bowel obstruction can be found by ultrasound. It can not be treated in-utero but has a high success rate with surgical correction shortly after birth. Babies with bowel obstructions should be delivered at a hospital with a NICU and a pediatric surgeon. The baby will need to stay in the NICU until they are able to eat without support and are gaining weight. *Babies born with bowel obstruction have a 10% chance of having cystic fibrosis if both parents are carriers.

Signs: a segment of dilated bowel seen on ultrasound, and polyhydramnios

Hydrops Fetalis

Hydrops Fetalis– is when large amounts of fluid build up in fetal tissues leading to heart failure. Treatment of hydrops during pregnancy may not be possible, so early delivery is often recommended if symptoms are severe. After delivery treatment includes management of breathing problems, removal of excess fluid from the space around the heart, lungs, and stomach, and medications to help the kidneys remove the fluid. 

There are two kinds of hydrops:

  • Immune hydrops fetalis is when the mother’s immune system causes the breakdown of red blood cells in the fetus. It is caused by maternal/fetal blood incompatibility. With the invention of isoimmunization, this type of hydrops is becoming far less common.
  • Non-immune hydrops fetalis is when another disease or complication interferes with the baby’s ability to effectively manage fluid. It is the most common type of hydrops and can be caused by fetal anemia, infection, heart or lung defects, chromosomal disorders, or liver disease.
Signs: polyhydramnios, thickened placenta, enlarged fetal liver, spleen, or heart, and excess fluid in the fetal abdomen. Signs after birth: pale coloring, severe swelling, enlarged liver or spleen, and breathing problems in the baby. 


Hypotonia is low muscle tone in a baby, usually detected at birth or in early childhood. While the signs of hypotonia may be relatively easy to recognize, the cause behind it can be much harder to detect. Hypotonia can be caused by problems with the nerves or muscles, or it can be a result of injury, illness, or inherited disorder. Occasionally there is no linked cause for hypotonia. If hypotonia is suspected, blood tests, CT scans, and MRIs may be used to try to determine the cause. Treatment depends largely on what is causing the hypotonia but usually includes physical and occupational therapies.

Signs: “floppy” baby, poor head control, and delayed gross and fine motor skills.

Kleefstra Syndrome

Kleefstra Syndrome is a rare genetic anomaly that almost always occurs spontaneously. In Kleefstra Syndrome, a small part of chromosome 9 is missing (called a microdeletion). It presents with a wide range of characteristics, depending on the size of the deletion, but it is most commonly characterized by developmental delay, intellectual disorder, severe speech delay, distinctive facial features, and low muscle tone. Children with Kleefstra Syndrome can greatly benefit from early intervention therapies.

Signs: short, upturned nose, coarse facial features, pronounced cupid’s bow or a “v” shaped apex in the upper lip, turned out lower lip, wide-set eyes, severe speech delay, global developmental delay, and low muscle tone.


Laryngomalacia– is a congenital disorder that affects the structure of the larynx (voice box), causing it to be floppy and fall over the opening of the airway and partially block it. The most common symptom of Laryngomalacia is noisy breathing. Laryngomalacia is usually diagnosed after birth when an infant shows clinical signs and can be confirmed by further testing. Most cases of laryngomalacia clear up on their own between 18-20 months; for those that don’t, medication or surgery may be needed.

Signs: noisy breathing, problems with eating, breathing, and gaining weight. 

Maternal Diabetes

Materna Diabetes is a condition in which insulin in the body is not able to break down sugar and carbohydrates into energy, resulting in high blood sugar levels. Uncontrolled diabetes can lead to macrosomia (a large baby), shoulder dystocia, nerve damage in the baby due to shoulder dystocia, a higher chance of c-section delivery, preeclampsia, premature birth, development of life-threatening hypoglycemia in mom or in the baby after delivery, miscarriage, or stillbirth.

There are 3 common types of diabetes, each of which may require a different form of treatment/management. Every form should require daily blood sugar monitoring and rapid treatment when there are signs of hypoglycemia.
  • Type 1 Diabetes – is when the pancreas makes little or no insulin at all and must be controlled by daily insulin use. 
  • Type 2 Diabetes – is when either too little insulin is made, or the body isn’t able to use the insulin it has to properly break down sugar and carbohydrates. Type 2 Diabetes is usually controlled by a combination of diet, exercise, pills, and insulin.
  •  *Uncontrolled Type 1 and Type 2 Diabetes are associated with a higher risk of birth defects due to high blood sugar levels in very early pregnancy.
  • Gestational Diabetes – is when the onset of glucose intolerance symptoms first happens during pregnancy. Gestational diabetes can usually be diagnosed by a glucose tolerance test between 24-28 weeks gestation. Treatment for Gestational Diabetes usually involves diet and exercise modifications and sometimes requires insulin treatment.
Signs: usually none, but sometimes excessive thirst, frequent urination of large amounts, fatigue, and sugar in the urine.


Maternal Hashimoto's Disease

Maternal Hashimoto’s Disease – is an autoimmune disorder that damages the thyroid and is the most common cause of hypothyroidism. Hypothyroidism is treatable with medicine, even during pregnancy, but left untreated it can cause serious problems for mom and baby. Untreated hypothyroidism during early pregnancy has been linked to birth defects that can cause Polyhydramnios, including problems with the heart, kidneys, and central nervous system. The biggest sign of Hashimoto’s is swelling in the front of the neck (goiter).  Hashimoto’s is treated with daily thyroid hormone pills. During pregnancy, patients will need to be closely monitored to make sure the thyroid is functioning properly and make necessary adjustments to thyroid treatment.

Signs: goiter, feeling tired,  feeling cold, constipation, weight gain, and heavy periods.

Maternal Uremia

Maternal Uremia is a dangerous condition in which the kidneys are no longer able to function properly causing a dangerous build-up of toxins in the blood. Uremia is treated by dialysis or kidney transplant. Women with a diagnosis of uremia are usually advised NOT to become pregnant. Pregnancy in a uremic mother undergoing dialysis is associated with a higher risk of spontaneous abortion, hypertension, preeclampsia, polyhydramnios, preterm labor, and premature birth. Research is limited, and prognosis tends to be very poor in cases of maternal uremia, although some research (like this study) is pointing to the effective management of uremic patients during pregnancy. 

Signs: nausea, vomiting, fatigue, anorexia, weight loss, muscle cramps, pruritis, mental status changes, visual disturbances, and increased thirst.


Micrognathia– is a condition in which the baby’s lower jaw is undersized and can cause trouble with breathing and feeding. It can be an inherited trait, a symptom of another genetic disorder, or it can sometimes occur for no obvious reason. Micrognathia is fairly common in infants and it can correct itself as they grow. Micrognathia can be diagnosed by a combination of a physical exam, imaging scans, and sleep studies. Many people with Micrognathia can be treated by non-surgical therapies designed to keep the airway open while sleeping. In cases where breathing is severely impaired, surgical procedures may be needed.

Signs: temporary pauses in breathing, feeding problems, noisy breathing, or trouble sleeping.

Noonan Syndrome

Noonan Syndrome is a genetic disorder that can prevent normal development in many different parts of the body. Commonly affected parts of the body include having distinct facial features, heart defects, growth issues (short stature is common), musculoskeletal deformities, learning disabilities, vision and hearing problems, bleeding problems, lymphatic system disorders, genital and kidney problems, and skin conditions.  Noonan Syndrome can be inherited or it can occur as a spontaneous mutation. If a family history of Noonan Syndrome exists, prenatal testing is available for the baby. If Noonan is suspected sometime after birth, molecular genetic testing can help to confirm the diagnosis. Treatment for Noonan Syndrome focuses on the management of the symptoms and can include medications, surgeries, growth hormone therapy, and physical or speech therapies.

Signs: characteristic facial appearance, short stature, congenital heart defect, a broad or webbed neck, minor eye problems, bleeding problems or abnormal bruising, unusual chest shape with widely spaced and low set nipples, developmental delay, and undescended testes.

Placental Chorioangioma

Placental chorioangioma is the most common type of benign mass on the placenta. It is usually located on the fetal side of the placenta near the umbilical cord insertion. Placental chorioangiomas can often be detected by an alpha-fetoprotein blood test or by ultrasound. Some small chorioangiomas do not cause any problems, but larger ones have been associated with Polyhydramnios, fetal hydrops, fetal anemia, thrombocytopenia, IUGR, and IUFD. Treatment depends on the severity of the case and mostly involves the management of symptoms caused by the chorioangioma.

Sings in mom: polyhydramnios, preterm labor, preeclampsia, placental abruption, excessive bleeding, or problems with blood clotting. Signs in baby: heart failure, hydrops, hemolytic anemia, birth defects, low platelet count, restricted growth, clotting disorders, and an enlarged heart.

Pleural Effusion

Pleural Effusion – also called Fetal Hydrothorax, is when there is an abnormal accumulation of fluid in the chest cavity between the lungs and the chest wall that causes compression of the surrounding structures. Pleural effusion can sometimes be caused by infection, heart conditions, or genetic anomalies. Pleural effusion can be detected by ultrasound during pregnancy. Most cases are mild and only require extra monitoring. After delivery, some babies with pleural effusion need help to breathe, and sometimes a chest tube may be placed to help drain fluid. Treatment will depend on the exact cause of the pleural effusion, but the prognosis for most cases is good.

Signs: usually seen on ultrasound before 32 weeks. Signs in baby: chest pain made worse with coughing or breathing, cough, fever or chills, rapid breathing, hiccups, and shortness of breath.

Prader-Willi Syndrome (PWS)

Prader-Willi Syndrome (PWS) – is a genetic disorder resulting from an abnormality on chromosome 15. PWS can be inherited or it can occur randomly. Genetic testing, specifically DNA methylation can confirm PWS. Treatment for PWS includes managing the symptoms using a variety of therapies and administration of human growth hormone to increase stature, decrease body fat, increase stamina and bone mineral density, and positively affect development and behavior.

Signs: low muscle tone at birth, small hands and feet, small stature, low lean body mass, early onset of childhood obesity, insatiable hunger, and intellectual disability.

Rh Incompatibility

Rh (Rhesus) Incompatibility and Isoimmunization happens when an RH negative mother is carrying an RH positive baby. The risk is that when the differing Rh types mix, mom’s negative blood cells will develop antibodies that attack the baby’s positive blood cells. This condition doesn’t affect mom and is easily preventable with good prenatal care. Early blood tests will detect if a mother is Rh-negative, and a dose of Rhogam given at 28 weeks and again shortly after delivery can help prevent the mother’s body from creating antibodies against Rh-positive blood cells. Sometimes though, a mother has already developed antibodies to Rh-positive blood. This can happen from a previous miscarriage, abortion, ectopic pregnancy, trauma during pregnancy, amniocentesis, during the birth process, or from a blood transfusion. A blood test can be done to check for antibodies. If they are present, amniocentesis will detect if the baby is ill.

Signs: mom is Rh-negative and baby is Rh-positive, jaundice, lethargy, and low muscle tone.

Sacrococcygeal Teratoma

Sacrococcygeal Teratoma is a very rare, and usually benign, tumor that develops on the tailbone of a fetus. Sacrococcygeal Teratomas can be suspected when the uterus is larger than expected and are diagnosed by an alpha-fetoprotein blood test, or by ultrasound. Most sacrococcygeal teratomas do not cause major problems during pregnancy, occasionally though a very large or very fibrous teratoma can place a very high demand for blood on the heart of the fetus, leading to fetal hydrops or heart failure. For these instances, fetal surgery or early delivery may be necessary. All cases of sacrococcygeal teratoma require surgical removal of the tumor after birth and the prognosis after surgery is very good.

Signs: polyhydramnios, sometimes preeclampsia, a tumor seen on ultrasound, and baby unable to urinate or have a bowel movement.

Skeletal Dysplasias

Skeletal Dysplasias are a classification of more than 200 disorders that affect skeletal bone and cartilage growth, resulting in “dwarfism”. Skeletal dysplasias are usually picked up on the 20-week anatomy scan. Further scans and genetic testing is often required to determine the cause and type of dysplasia, which will then determine the course of treatment. It is often hard to determine the type of skeletal dysplasia during pregnancy, so more testing will likely be done on the newborn shortly after birth. The prognosis for most types of skeletal dysplasia is good.

Signs: short stature, large head with prominent forehead, long trunk with shorter arms and legs, brittle teeth and bones, hearing loss, cleft palate, vision problems, and hydrocephalus.

ToRCH Infection

TORCH Infection – is a group of congenital infections that are passed from mother to baby during pregnancy and remain present in the baby after birth. TORCH infections can cause fetal anemia as well as other congenital defects and problems after birth, depending on the specific virus. 

 TORCH stands for:
  •  Toxoplasmosis
  • Other (Syphilis, Varicella, Mumps, Parvovirus, HIV)
  • Rubella
  • Cytomegalovirus
  • Herpes Simplex

 TORCH infections can be detected during pregnancy by a blood test called a TORCH screen.

Signs: stillbirth, IUGR, or preterm labor, lethargic baby, fever, difficulty feeding,  enlarged liver or spleen, anemia, petechia or purpura, jaundice, and chorioretinitis. 

Tracheoesophageal Fistula

Tracheoesophageal Fistula, also called TEF, is a condition that affects the trachea, or windpipe, and often presents along with Esophageal Atresia. With TEF, it is common to see a connection between the esophagus and the trachea allowing liquid to be able to pass into the lungs which can cause pneumonia and other problems. This condition also requires surgical correction. *Approximately 50% of babies born with AE or TEF also have another birth defect.

Signs: frothy, white bubbles in the mouth, coughing or choking when feeding, vomiting, blue coloring of the skin especially while feeding, trouble breathing, and a very round, full stomach.


Twin to Twin Transfusion Syndrome

Twin to Twin Transfusion Syndrome (TTTS) is a rare complication affecting monochorionic identical twins or other higher-order multiples who share the same placenta and the network of blood vessels needed for development inside the womb. In TTTS, the network of blood vessels is unevenly distributed resulting in not enough blood supply in one baby and too much in the other. This can cause low urine output, oligohydramnios, IUGR, and fetal death in the donor twin and excessive urine output, polyhydramnios, and heart failure in the recipient twin. TTTS can be detected by an ultrasound that measures oligohydramnios in one twin and polyhydramnios in the other. Treatments for TTTS depend on when the transfusions began and can range from treatment of the affected blood vessels to early delivery to the treatment of the symptoms caused by TTTS.

Signs in mom: a feeling of rapid growth of the uterus, a large uterus, abdominal pain or tightness, premature contractions, a sudden increase in weight, and swelling of the hands and feet in early pregnancy.

VACTERL Association

VACTERL Association (VATER Syndrome) is a disorder that affects several systems at once. VACTERL stands for Vertebral defects, Anal atresia, Cardiac defects, Tracheoesophageal Fistula, Renal anomalies, and Limb abnormalities. There is no test for VACTERL Association, so babies are diagnosed with it based on clinical findings of at least 3 of these characteristics present at the same time. Treatment involves managing the individual symptoms and can involve surgery for atresias and severe cardiac problems, medications, and a variety of therapies. Unless there are severe heart complications, prognosis for babies with VACTERL Association is usually good.

Signs: With the bones: missing or extra bones in the spine, abnormally shaped bones, bones fused together, scoliosis, or extra ribs. With the anus: a swollen belly, vomiting, or no stool movements caused by a thin covering over the anus or there is no connection between the rectum and the anus. With the heart: VSD, atrial septal defect, tetralogy of Fallot, hypoplastic left heart syndrome, patent ductus arteriosus, or transposition of the great arteries which can cause trouble breathing, shortness of breath, blue coloring of skin, fatigue, abnormal heart rhythm, fast heart rate, heart murmur, poor eating, and no weight gain. With TEF: breathing food into the lungs, coughing or choking while feeding, vomiting, blue color of the skin, trouble breathing, swollen belly, and poor weight gain. With renal defects: poorly formed kidneys, kidneys in the wrong place, blockage of urine out of the kidneys, or a backup of urine from the bladder into the kidneys. With the limbs: missing or poorly developed thumbs, extra fingers or toes, webbed fingers or toes, or poorly developed forearms.

X-Linked Myotubular Myopathy

X-linked Myotubular Myopathy (XLMTM) is an extremely rare (1 in 50,000 births) condition that affects skeletal muscles used for movement and causes muscle weakness and decreased muscle tone. XLMTM almost always occurs in males and the symptoms are evident at birth. Muscle weakness usually causes feeding and breathing problems in newborns. Most people with XLMTM do not have the muscle strength to breathe on their own so artificial ventilation is required, and many live only into early childhood.

Signs: male baby, extreme muscle weakness and hypotonia right after birth, respiratory distress and feeding difficulty causing a prolonged hospital stay (average 90 days), early death, motor development delay, high forehead, underdevelopment of the middle face, long and narrow head with a long face, high arched palate, misaligned teeth, ptosis, nearsightedness, large head, infants >90th percentile for length, and abnormally long fingers and toes.



Currently, there are no published studies that link autism to Polyhydramnios. However, autism is linked to some syndromes that are known to cause Polyhydramnios. The best people to ask this question to are the ones who have lived it, so why not check out a Polyhydramnios support group and ask about their experience with this? Check out our list of Polyhydramnios support groups here.

In some cases, amniotic fluid may be reduced by managing the underlying condition. For example, a diabetic diet may help reduce fluid in women with high blood sugar levels. Amnioreduction and indomethacin have also been used to reduce amniotic fluid, although these methods are only recommended under extreme circumstances. Some women have also reported a reduction in amniotic fluid after using the herb Nat Mur, however, we recommend you research this product and speak to your healthcare provider before trying it for yourself. Read more on the management of Polyhydramnios here.

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Diagnosis & Testing of Polyhydramnios – Following a Polyhydramnios diagnosis, routine testing should include a GTT, NSTs, BPPs, and growth scans, with additional testing in more severe cases.

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