Overview 

Potter syndrome is a rare and congenital (present from birth) condition, estimated to affect between 1 in 4,000 to 10,00 births.¹ 

Also referred to as the Potter or oligohydramnios sequence, Potter syndrome causes abnormal internal organ development in the foetus (unborn baby). The condition is usually terminal (fatal), but symptoms vary between different infants.¹

In the most severe cases, major organs like the heart, lungs and kidneys do not develop properly and cause fatality at or shortly after birth¹. Milder cases with more complete organ development and function can show an improved life expectancy, but with chronic (long-term) complications that require intensive treatment and management.²

Medical understanding has progressed significantly since early identification of Potter syndrome. Fortunately, our advanced understanding of the condition means that medics can make a swifter diagnosis and prepare the prospective parents from an earlier stage as to what to expect during pregnancy and birth. Treatment options for the infant have significantly advanced, thereby optimising the expected outcome (the prognosis) of Potter syndrome for the infant.

Potter syndrome in the 20th century

Dr Edith Potter – as her name may suggest – was instrumental to our modern, comprehensive understanding of Potter syndrome. 

Over the span of a decade, Dr Potter conducted approximately 5000 post-mortem examinations on infants who had passed away during the perinatal stage (from pregnancy to a year post-birth).³ In her 1946 report on these autopsies, she noted that 20 of these infants shared common characteristics:

• missing kidneys (bilateral renal agenesis)
• distinctive facial characteristics (known as ‘Potter facies’)
• underdeveloped lungs (pulmonary hypoplasia) 

These face and lung deformities had not previously been associated with developmental kidney disorders, indicating there was another unknown and more potent factor disturbing embryonic development across the seemingly unconnected organ systems⁴. 

Dr Potter noted that infants born alive with kidney abnormalities were mostly cyanotic (bluish in colour), had breathing difficulties, and died shortly after birth. From these observations, she concluded that kidney function in infancy was not necessary for foetal survival within the uterus and that lung deformities were the most fatal characteristics.⁴

Decades later, following Dr Potter’s meticulous reporting, she and other clinicians in the same field were able to connect embryonic kidney, lung, and facial developmental issues with the underlying cause of prolonged amniotic fluid depletion.^5,6

From these analyses, the sequence of events leading up to what is now termed Potter syndrome is understood, shaping the diagnostic process and understanding how to optimize prognosis through a number of treatment interventions.⁴

Potter syndrome in the 21st century 

Definition and cause 

Thanks to the work of Dr Potter and her contemporaries, we understand that Potter syndrome is the developmental disorder caused by low levels of amniotic fluid (oligohydramnios) in the uterus during pregnancy.

Amniotic fluid supports the foetus by providing nutrients and essential components (eg. hormones, antibodies), stimulating body functions (eg. breathing in and swallowing the fluid), and creating space for growth.¹

The production of amniotic fluid changes over the course of the pregnancy. During early stages, it is made up of water and nutrients from the parent’s own body, but after 16-20 weeks the baby contributes to the fluid by drinking it and urinating.¹ With impaired replenishment and maintenance of amniotic fluid levels, foetuses lack cushioning and protection against pressure from the uterine wall. 

Several factors have been identified in affecting amniotic fluid levels and as possible causes for Potter syndrome. Factors relating to foetal development may be:¹

• Underdeveloped or missing kidneys (renal agenesis) 
• Polycystic kidney disease
• Prune belly syndrome (Eagle-Barett syndrome)
• Blockages of the urinary tract

Factors affecting the pregnant parent include:¹

• Unmanaged conditions, such as Type 1 diabetes
• Ruptured membranes of the uterus, permitting amniotic fluid leakage

Symptoms

Facial and physical characteristics

The pressure from insufficient amniotic fluid compresses the developing foetus, causing facial and skeletal abnormalities which are characteristic to Potter syndrome.⁷

Facial characteristics (Potter facies)

• Flattened nose, receding chin (retrognathia), prominent eye folds (epicanthal folds), low-sitting ears

Eye abnormalities⁸

• Cataracts, abnormal blood vessel changes (vascular malformations) in the optic disc, prolapse of the eye lens, expulsive hemorrhage

Skeletal deformations²

• Short limbs, spinal deformities (such as hemivertebrae, caudal regression)

Prune belly (Eagle-Barret syndrome)²

• Undeveloped testes in babies assigned male at birth (AMAB)
• Poorly developed abdominal muscles
• Enlarged bladder and tubes draining from the bladder (megaureter) 

Other

• Joint extension difficulties or contractures
• Small for gestational age

Underdeveloped organs

Development of foetal organs under compression leads to organ abnormalities that can cause extremely serious and life-threatening conditions. These include:

Kidney conditions

• Underdeveloped or missing kidneys (renal agenesis)

Lung conditions²

• Chronic lung disease, respiratory distress, pulmonary hyperplasia

Congenital heart conditions²

• (including ventricular septal defect, tetralogy of Fallot, endocardial cushion defect, patent ductus arteriosus)

Diagnosis

Following the reports and observations from Dr Potter, clinicians can now diagnose Potter syndrome during pregnancy with a prenatal exam.¹

Regular check-ups using ultrasound imaging techniques will be used to monitor levels of amniotic fluid in the uterus, and assess the physical development of the foetus.¹

After birth, a physician will assess the newborn through a physical exam, looking for symptoms including:¹

• Minimal urine production
• Abnormal facial characteristics
• Breathing difficulties

Further measures will be offered to confirm diagnosis, including:¹

• Tests checking electrolyte and enzyme levels are normal in the blood and urine 
• Genetic blood tests to identify gene responsible for symptoms
• Echocardiogram to identify heart abnormalities
• Imaging of lungs, kidneys and urinary tract through ultrasound, X-ray or MRI

Management

Treatment for Potter syndrome varies depending on how severely the infant’s lungs and heart are affected.

If the foetal chest is compressed for long durations, resulting in oligohydramnios (too little amniotic fluid), the lungs may not have formed enough tissue to function following birth. In some cases, intensive interventions are not sustainable for newborns and families may opt for neonatal palliative care, focusing on infant comfort and bonding.¹

Surviving birth, treatment may be available to manage life-threatening symptoms. These options include:¹

• Breathing support through a ventilator
• Medications to help with lung function 
• Corrective surgery to alleviate the urinary tract blockage
• Surrey to improve feeding via nasogastric tube, or nutritional support through an IV tube
• Dialysis to filter water through the blood if kidney function is impaired
• Kidney transplantation might be considered if dialysis proves unsuccessful over time

In some situations treatment can even begin before birth. Diagnosis early in pregnancy (before 22 weeks) may provide the opportunity for interventions such as amnioinfusion, a procedure where fluid is introduced into the amniotic sac to compensate for low fluid levels.¹

FAQs

Are there any cases of babies surviving Potter Syndrome?

Yes, the daughter of US Congresswoman Jaime Herrera Buetler (born in 2013) was the first child to survive Potter syndrome with missing kidneys (bilateral renal agenesis).⁹

A few weeks before the birth, Ms Buetler was administered a series of saline solution injections into her womb to alleviate pressure and aid with the development of her daughter’s lungs. The baby was born with functional lungs, and did not require breathing assistance through a ventilator – deeming the injections a successful measure. The infant received kidney dialysis, until she was able to receive a kidney transplant two years after birth.¹⁰

Is Potter syndrome inherited?

Babies can inherit some causes that contribute to developing Potter syndrome, but it isn't classed as a genetic condition.¹ Some inherited risk factors of the syndrome include:

• Polycystic kidney disease: this can be inherited if the genes are passed down from one parent (autosomal dominant) or in an autosomal recessive manner, whereby the infant must inherit a copy of the faulty gene from each parent to show symptoms to have the disease¹
• Renal agenesis: inherited mutations in genes involved in kidney development (including FGF20 or GREB1L genes) can lead to improper kidney development. Similarly, renal agenesis can be passed to the child in an autosomal dominant or recessive manner^11,12
• Random (sporadic) genetic changes¹ 

Is Potter syndrome sex-specific?

No, but it does primarily affect babies assigned male at birth (AMAB).¹³

Summary 

Potters syndrome has evolved significantly in its clinical understanding and management since its first characterisation by Dr Edith Potter. 

Her foundational work linked kidney malformations to a sequence of developmental complications caused by reduced amniotic fluid, which has now become a diagnosable condition with the aid of parallel technological and medical developments (such as genetic testing and different imaging techniques).

Today, early diagnosis allows for more accurate prognoses and better informed decisions for expecting families. In select cases, modern interventions offer hope. In many more severe cases, early diagnosis aids the emotional preparation for families who are experiencing Potter syndrome fatality.