The outcome of Potter's Sequence is poor. A series of 23 patients in 2007 recorded 7 deaths, 4 in the neonatal period. All 16 survivors have chronic kidney disease, with half developing end stage renal failure (median age 0.3 years, range 2 days to 8.3 years). Survivors had growth impairment (44%) and cognitive and motor development delay (25%)

The first child to survive Bilateral Renal Agenesis (BRA), Abigail Rose Herrera Beutler, was born on July 2013 to US Congresswoman Jaime Herrera Beutler.

A few weeks before she was born, Dr. Jessica Bienstock, a professor of maternal-fetal medicine at Johns Hopkins Hospital, administered a series of saline solution injections into the mother's womb to help the baby's lungs to develop. After Abigail was born, the procedure was considered a success. The infant did not need artificial respiration and could breathe on her own. Her parents kept her on kidney dialysis at home until old enough for a kidney transplant. On February 8, 2016, at the age of two, Abigail received a kidney from her father at the Lucile Packard Children's Hospital Stanford in California.

The Potter sequence is due to restricted ability for certain organs to grow due to severe oligohydramnios.

In one study, the causes leading to Potter sequence were bilateral renal agenesis in 21.25% of cases; cystic dysplasia in 47.5%; obstructive uropathy in 25%; and others in 5.25%.

Renal agenesis is a medical condition in which one (unilateral) or both (bilateral) fetal kidneys fail to develop.

Unilateral and Bilateral Renal Agenesis in humans, mice and zebra fish has been linked to mutations in the gene GREB1L. It has also been associated with mutations in the genes "RET" or "UPK3A". in humans (see Rosenblum et al 2017 for review) and mice respectively.

Most fetuses with triploidy do not survive to birth, and those that do usually pass within days. As there is no treatment for Triploidy, palliative care is given if a baby survives to birth. If Triploidy is diagnosed during the pregnancy, termination is often offered as an option due to the additional health risks for the mother (preeclampsia, a life-threatening condition, or choriocarcinoma, a type of cancer). Should a mother decide to carry until term or until a spontaneous miscarriage occurs, doctors will monitor her closely in case either condition develops.

Mosaic triploidy has an improved prognosis, but affected individuals have moderate to severe cognitive disabilities.

If left untreated, the pump twin will die in 50–75% of cases.

After diagnosis, ultrasound and amniocentesis are used to rule out genetic abnormalities in the pump twin. A procedure may then be performed which will stop the abnormal blood flow. The acardiac twin may be selectively removed. The umbilical cord of the acardiac twin may be surgically cut, separating it from the pump twin, a procedure called fetoscopic cord occlusion. Or a radio-frequency ablation needle may be used to coagulate the blood in the acardiac twin's umbilical cord. This last procedure is the least invasive. These procedures greatly increase the survival chances of the pump twin, to about 80%.

The pump twin will be monitored for signs of heart failure with echocardiograms. If the pump twin's condition deteriorates, the obstetrician may recommend early delivery. Otherwise, the pregnancy continues normally. Vaginal birth is possible unless the fetus is in distress, although it is recommended that the delivery take place at a hospital with NICU capabilities.

A Cochrane review concluded that "simple maternal hydration appears to increase amniotic fluid volume and may be beneficial in the management of oligohydramnios and prevention of oligohydramnios during labour or prior to external cephalic version."

In severe cases oligohydramnios may be treated with amnioinfusion during labor to prevent umbilical cord compression. There is uncertainty about the procedure's safety and efficacy, and it is recommended that it should only be performed in centres specialising in invasive fetal medicine and in the context of a multidisciplinary team.

In case of congenital lower urinary tract obstruction, fetal surgery seems to improve survival, according to a randomized yet small study.

In 2008 researchers found autosomal dominant mutations in the RET and GDNF genes to be linked to renal agenesis in unrelated stillborn fetuses through PCR and direct sequence analysis . In the study, DNA from 33 stillborn fetuses were sequenced for mutations in RET, GDNF and GFRA1. Nineteen of the fetuses had BRA, ten had URA and 4 had congenital renal dysplasia. Seven of the 19 BRA fetuses were found to have a mutation in the RET gene (37%), while two of the ten URA fetuses did (20%). One of the URA fetuses had two RET mutations and one GDNF mutation. There were no GFRA1 mutations found.

However, the results of Skinner et al. study were questioned by a more recent study with a larger number of cases . In this study 105 fetuses were analyzed. Sixty-five fetuses had BRA while 24 had URA with an abnormal contralateral kidney. Mutations in the RET gene were only found in seven of the fetuses (6.6%).

In 2014 researchers found autosomal recessive mutations in ITGA8 in three members of two unrelated families utilizing Exome Sequencing . One of the families was consanguineous.

In 2017 researchers identified heritable autosomal dominant mutations in the gene GREB1L in two unrelated families as being the cause of both BRA and URA utilizing Exome Sequencing and direct sequencing analysis . This is the first reported genetic lesion implicated in the activation of Retinoic Acid Receptor (RAR) Targets that has been associated with renal agenesis in humans. The researchers found two different GREB1L mutations, each being unique to their respective pedigrees. In total, there were 23 individuals analyzed between the two families, four of which had BRA and five of which had URA. GREB1L mutations were identified in all of the affected individuals as well as in three unaffected family members, demonstrating incomplete penetrance and variable expressivity.

There are several hundred to perhaps several thousand genes that, if they had the right kind of mutation, could lead to renal agenesis in humans. It is possible that each individual or family experiencing renal agenesis has a unique gene or genetic mutation causing the condition due to the fact that there are so many genes that are critical to proper renal development. See Rosenblum S et al. for an excellent review of Congenital abnormalities of the Kidney and Urinary Tract

Chromosomal anomalies have been associated with BRA in certain cases (chromosomes 1, 2, 5 and 21), but these anomalies were not inherited and have not been observed in subsequent cases. Additionally, neither extreme substance abuse or environmental factors (high power line, mercury, ground water issues, etc.) have been reported to be linked to an increased incidence of BRA or other cause of Potter sequence. However, renal agenesis and other causes of oligohydramnios sequence have been linked to a number of other conditions and syndromes to include Down syndrome, Kallmann syndrome, branchio-oto-renal syndrome and others.

While there is no cure for BGS, symptoms can be treated as they arise. Surgery shortly after birth can repair craniosynostosis, as well as defects in the hand to create a functional grasp. There are risks associated with untreated craniosynostosis, therefore surgery is often needed to separate and reshape the bones. Since patients with a RECQL4 mutation may be at an increased risk of developing cancer, surveillance is recommended.

Management has three components: interventions before delivery, timing and place of delivery, and therapy after delivery.

In some cases, fetal therapy is available for the underlying condition; this may help to limit the severity of pulmonary hypoplasia. In exceptional cases, fetal therapy may include fetal surgery.

A 1992 case report of a baby with a sacrococcygeal teratoma (SCT) reported that the SCT had obstructed the outlet of the urinary bladder causing the bladder to rupture in utero and fill the baby's abdomen with urine (a form of ascites). The outcome was good. The baby had normal kidneys and lungs, leading the authors to conclude that obstruction occurred late in the pregnancy and to suggest that the rupture may have protected the baby from the usual complications of such an obstruction. Subsequent to this report, use of a vesicoamniotic shunting procedure (VASP) has been attempted, with limited success.

Often, a baby with a high risk of pulmonary hypoplasia will have a planned delivery in a specialty hospital such as (in the United States) a tertiary referral hospital with a level 3 neonatal intensive-care unit. The baby may require immediate advanced resuscitation and therapy.

Early delivery may be required in order to rescue the fetus from an underlying condition that is causing pulmonary hypoplasia. However, pulmonary hypoplasia increases the risks associated with preterm birth, because once delivered the baby requires adequate lung capacity to sustain life. The decision whether to deliver early includes a careful assessment of the extent to which delaying delivery may increase or decrease the pulmonary hypoplasia. It is a choice between expectant management and active management. An example is congenital cystic adenomatoid malformation with hydrops; impending heart failure may require a preterm delivery. Severe oligohydramnios of early onset and long duration, as can occur with early preterm rupture of membranes, can cause increasingly severe PH; if delivery is postponed by many weeks, PH can become so severe that it results in neonatal death.

After delivery, most affected babies will require supplemental oxygen. Some severely affected babies may be saved with extracorporeal membrane oxygenation (ECMO). Not all specialty hospitals have ECMO, and ECMO is considered the therapy of last resort for pulmonary insufficiency. An alternative to ECMO is high-frequency oscillatory ventilation.

In 1908, Maude Abbott documented pulmonary hypoplasia occurring with certain defects of the heart. In 1915, Abbott and J. C. Meakins showed that pulmonary hypoplasia was part of the differential diagnosis of dextrocardia. In 1920, decades before the advent of prenatal imaging, the presence of pulmonary hypoplasia was taken as evidence that diaphragmatic hernias in babies were congenital, not acquired.

Some doctors recommend complete bed-rest for the mother coupled with massive intakes of protein as a therapy to try to counteract the syndrome. Research completed shows these nutritional supplements do work. Diet supplementation was associated with lower overall incidence of TTTS (20/52 versus 8/51, P = 0.02) and with lower prevalence of TTTS at delivery (18/52 versus 6/51, P = 0.012) when compared with no supplementation. Nutritional intervention also significantly prolonged the time between the diagnosis of TTTS and delivery (9.4 ± 3.7 weeks versus 4.6 ± 6.5 weeks; P = 0.014). The earlier nutritional regimen was introduced, the lesser chance of detecting TTTS ( P = 0.001). Although not statistically significant, dietary intervention was also associated with lower Quintero stage, fewer invasive treatments, and lower twin birth weight discordance. Diet supplementation appears to counter maternal metabolic abnormalities in monochorionic twin pregnancies and improve perinatal outcomes in TTTS when combined with the standard therapeutic options. Nutritional therapy appears to be most effective in mitigating cases that are caught in Quintero Stage I, little effect has been observed in those that are beyond Stage I.

Patients with abnormal cardiac and kidney function may be more at risk for hemolytic uremic syndrome

This procedure involves removal of amniotic fluid periodically throughout the pregnancy under the assumption that the extra fluid in the recipient twin can cause preterm labor, perinatal mortality, or tissue damage. In the case that the fluid does not reaccumulate, the reduction of amniotic fluid stabilizes the pregnancy. Otherwise the treatment is repeated as necessary. There is no standard procedure for how much fluid is removed each time. There is a danger that if too much fluid is removed, the recipient twin could die. This procedure is associated with a 66% survival rate of at least one fetus, with a 15% risk of cerebral palsy and average delivery occurring at 29 weeks gestation.

The goals of treatment in infants with Robin sequence focus upon breathing and feeding, and optimizing growth and nutrition despite the predisposition for breathing difficulties. If there is evidence of airway obstruction (snorty breathing, apnea, difficulty taking a breath, or drops in oxygen), then the infant should be placed in the sidelying or prone position, which helps bring the tongue base forward in many children. One study of 60 infants with PRS found that 63% of infants responded to prone positioning (Smith and Senders, 2006, Int J Pediatr Oto). 53% of the infants in this study required some form of feeding assistance, either nasogastric tube or gastrostomy tube feedings (feeding directly into the stomach). In a separate study of 115 children with the clinical diagnosis of PRS managed at 2 different hospitals in Boston (Evans et al., 2006, In J Pediatr Oto), respiratory distress was managed successfully in 56% without an operation (either by prone positioning, short term intubation, or placement of a nasopharyngeal airway). In this study, gastrostomy tube feeding were placed in 42% of these infants due to feeding difficulties.

Gastroesophageal reflux (GERD) seems to be more prevalent in children with Robin sequence (Dudkiewicz, March 2000, CPCJ). Because reflux of acidic contents in the posterior pharynx and upper airway can intensify the symptoms of Robin sequence, specifically by worsening airway obstruction, it is important to maximize treatment for GER in children with PRS and reflux symptoms. Treatment may include upright positioning on a wedge (a tucker sling may be needed if the baby is in the prone position), small and frequent feedings (to minimize vomiting), and/or pharmacotherapy (such as proton pump inhibitors).

In nasopharyngeal cannulation (or placement of the nasopharyngeal airway or tube), the infant is fitted with a blunt-tipped length of surgical tubing (or an endotracheal tube fitted to the child), which is placed under direct visualization with a laryngoscope, being inserted into the nose and down the pharynx (or throat), ending just above the vocal cords. Surgical threads fitted through holes in the outside end of the tube are attached to the cheek with a special skin-like adhesive material called 'stomahesive', which is also wrapped around the outside end of the tube (but not over the opening at the end) to keep the tube in place. This tube or cannula, which itself acts as an airway, primarily acts as a sort of "splint" which maintains patency of the airway by keeping the tongue form falling back on the posterior pharyngeal wall and occluding the airway, therefore preventing airway obstruction, hypoxia and asphyxia. Nasopharyngeal airways are not available at every center, however, when available, nasopharyngeal cannulation should be favored over the other treatments mentioned in this article, as it is far less invasive; it allows the infant to feed without the further placement of a nasogastric tube. This treatment may be utilized for multiple months, until the jaw has grown enough so that the tongue assumes a more normal position in the mouth and airway (at birth, the jaws of some infants are so underdeveloped that only the tip of the tongue can be seen when viewed in the throat). Some institutions discharge the infant home with a nasopharyngeal tube in place (Citation: KD Anderson, May 2007, CPCJ).

Distraction osteogenesis (DO), also called a "Mandibular Distraction", can be used to correct abnormal smallness of one or both jaws seen in patients with Robin Sequence. Enlargement of the lower jaw brings the tongue forward, preventing it from obstructing the upper airway. The process of DO begins with preoperative assessment. Doctors use three-dimensional imaging to identify the parts of the patient's facial skeleton that need repositioning and determine the magnitude and direction of distraction. They may then select the most appropriate distraction device or sometimes have custom devises fabricated. When possible, intraoral devices are used.

DO surgery starts with an osteotomy (surgical division or sectioning of bone) followed by the distraction device being placed under the skin and across the osteotomy. A few days later, the two ends of the bone are very gradually pulled apart through continual adjustments that are made to the device by the parents at home. The adjustments are made by turning a small screw that protrudes through the skin, usually at a rate of 1 mm per day. This gradual distraction leads to formation of new bone between the two ends. After the process is complete, the osteotomy is allowed to heal over a period of six to eight weeks. A small second surgery is then performed to remove the device.

The cleft palate is generally repaired between the ages of 6½ months and 2 years by a plastic or maxillofacial surgeon. In many centres there is now a cleft lip and palate team comprising both of these specialties, as well as a coordinator, a speech and language therapist, an orthodontist, sometimes a psychologist or other mental health specialist, an audiologist, an otorhinolaryngologist (ENT surgeon) and nursing staff. The glossoptosis and micrognathism generally do not require surgery, as they improve to some extent unaided, though the mandibular arch remains significantly smaller than average. In some cases jaw distraction is needed to aid in breathing and feeding. Lip-tongue attachment is performed in some centres, though its efficacy has been recently questioned.

Triploidy affects approximately 1-2% of pregnancies, but most miscarry early in development. At birth, males with triploidy are 1.5 times more common than females.

Children affected with PRS usually reach full development and size. However, it has been found internationally that children with PRS are often slightly below average size, raising concerns of incomplete development due to chronic hypoxia related to upper airway obstruction as well as lack of nutrition due to early feeding difficulties or the development of an oral aversion. However, the general prognosis is quite good once the initial breathing and feeding difficulties are overcome in infancy. Most PRS babies grow to lead a healthy and normal adult life.

The most important medical problems are difficulties in breathing and feeding. Affected infants very often need assistance with feeding, for example needing to stay in a lateral(on the side) or prone(on the tummy) position which helps bring the tongue forward and opens up the airway. Babies with a cleft palate will need a special cleft feeding device (such as the Haberman Feeder). Infants who are unable to take in enough calories by mouth to ensure growth may need supplementation with a nasogastric tube. This is related to the difficulty in forming a vacuum in the oral cavity related to the cleft palate, as well as to breathing difficulty related to the posterior position of the tongue. Given the breathing difficulties that some babies with PRS face, they may require more calories to grow (as working of breathing is somewhat like exercising for an infant). Infants, when moderately to severely affected, may occasionally need nasopharyngeal cannulation, or placement of a nasopharyngeal tube to bypass the airway obstruction at the base of the tongue. in some places, children are discharged home with a nasopharyngeal tube for a period of time, and parents are taught how to maintain the tube. Sometimes endotracheal intubation or tracheostomy may be indicated to overcome upper respiratory obstruction. In some centers, a tongue lip adhesion is performed to bring the tongue forward, effectively opening up the airway. Mandibular distraction can be effective by moving the jaw forward to overcome the upper airway obstruction caused by the posterior positioning of the tongue.

Given that a proportion of children with Robin sequence will have Stickler syndrome, it is important that a child with PRS have an evaluation by an optometrist or ophthalmologist in the first year of life looking for myopia that can be seen in Stickler syndrome. Because retinal detachment that can occur in Stickler syndrome is a leading cause of blindness in children, it is very important to recognize and be thoughtful of this diagnosis.

The incidence of Fraser syndrome is 0.043 per 10,000 live born infants and 1.1 in 10,000 stillbirths, making it a rare syndrome.

Fetuses with polyhydramnios are at risk for a number of other problems including cord prolapse, placental abruption, premature birth and perinatal death. At delivery the baby should be checked for congenital abnormalities.

In medicine, a sequence is a series of ordered consequences due to a single cause.

It differs from a syndrome in that seriality is more predictable: if A causes B, and B causes C, and C causes D, then D would not be seen if C is not seen. However, in less formal contexts, the term "syndrome" is sometimes used instead of sequence.

Examples include:

- oligohydramnios sequence (also known as Potter sequence)

- Pierre Robin sequence

- Poland sequence

While there is no specific treatment for the underlying genetic cause of LFS; corrective procedures, preventive intervention measures and therapies may be considered in the treatment and management of the many craniofacial, orthopedic and psychiatric problems associated with the disorder. More pressing issues such as cardiac involvement or epileptic seizures should be routinely examined and monitored. Close attention and specialized follow-up care, including neuropshycological evaluation methods and therapies, and special education, should be given to diagnose and prevent psychiatric disorders and related behavioral problems such as psychosis and outbursts of aggression.

The incidence of VACTERL association is estimated to be approximately 1 in 10,000 to 1 in 40,000 live-born infants. It is seen more frequently in infants born to diabetic mothers. While most cases are sporadic, there are clearly families who present with multiple involved members.

The cause is not known but is often associated with some:

- fetal chromosomal anomalies

- intra uterine infections

- drugs; PG inhibitors, ACE inhibitors

- renal agenesis or obstruction of the urinary tract of the fetus preventing micturition such as posterior urethral valves in males

- intrauterine growth restriction (IUGR) associated with placental insufficiency

- "amnion nodosum"; failure of secretion by the cells of the amnion covering the placenta

- postmaturity (dysmaturity)

Aphalangy, hemivertebrae and urogenital-intestinal dysgenesis is an extremely rare syndrome, described only in three siblings. It associates hypoplasia or aplasia of phalanges of hands and feet, hemivertebrae and various urogenital and/or intestinal abnormalities. Intrafamilial variability is important as one sister had lethal abnormalities (Potter sequence and pulmonary hypoplasia), while her affected brother was in good health with normal psychomotor development at 6 months of age. Prognosis seems to depend mainly on the severity of visceral malformations. Etiology and inheritance remain unknown.

Twin reversed arterial perfusion sequence—also called TRAP sequence, TRAPS, or acardiac twinning—is a rare complication of monochorionic twin pregnancies. It is a severe variant of twin-to-twin transfusion syndrome (TTTS). The twins' blood systems are connected instead of independent. One twin, called the "acardiac twin" or "TRAP fetus", is severely malformed. The heart is missing or deformed, hence the name acardiac, as are the upper structures of the body . The legs may be partially present or missing, and internal structures of the torso are often poorly formed. The other twin is usually normal in appearance. The normal twin, called the "pump twin", drives blood through both fetuses. It is called "reversed arterial perfusion" because in the acardiac twin the blood flows in a reversed direction.

TRAP sequence occurs in 1% of monochorionic twin pregnancies and in 1 in 35,000 pregnancies overall.

The treatment options for autosomal recessive polycystic kidney disease, given there is no current cure, are:

- Medications for hypertension

- Medications and/or surgery for pain

- Antibiotics for infection

- Kidney transplantation(in serious cases)

- Dialysis (if renal failure)