Bilateral Renal Agenesis & Potter Sequence

Hearing a diagnosis of Bilateral Renal Agenesis (BRA) is a devastating moment for any parent. It is a time of profound grief and complex decisions. This condition means that neither of the baby’s kidneys has developed, which creates a series of physical challenges for the baby while still in the womb. Understanding the “why” behind these changes and the options available—ranging from comfort-focused care to experimental trials—can help you navigate this path with clarity and love.

The Connection Between Kidneys and Breath

It may seem strange that a problem with the kidneys affects the lungs, but in the womb, these systems are deeply linked. After the first trimester, the baby’s urine becomes the primary source of amniotic fluid ^[1]. When kidneys are absent, the baby cannot produce urine (anuria), leading to a complete lack of amniotic fluid, known as anhydramnios ^[2].

Amniotic fluid is more than just a cushion; it is essential for development:

• Lung Development: For a baby’s lungs to grow, they must be “washed” and expanded by amniotic fluid. Without this fluid, the lungs remain small and underdeveloped, a condition called pulmonary hypoplasia ^[3][4]. This is often the most critical challenge at birth.
• Physical Protection: Amniotic fluid provides space for the baby to move. Without it, the baby is compressed by the uterine walls. This pressure causes the physical features of Potter sequence, which can include flattened facial features (like a pressed nose or chin), low-set ears, and limb differences such as clubbed feet or joint stiffening (contractures) ^[2][5].

Navigating Your Options

Because BRA has traditionally been considered a terminal diagnosis, families are faced with incredibly difficult choices. There is no right or wrong path—only the path that is right for your family and your baby.

Comfort-Focused Palliative Care

Many families choose palliative care, which focuses entirely on the baby’s comfort and the family’s needs. The goal is to ensure the baby is not in pain and that you have as much meaningful time together as possible. This often includes:

• Standardized protocols for managing any respiratory distress or pain at birth ^[6].
• Prioritizing skin-to-skin contact and creating memories (such as photos or handprints) ^[7].
• Support from a multidisciplinary team, including counselors and spiritual care providers ^[8].
• Tissue Donation: For families choosing palliative care, some find comfort in discussing neonatal tissue donation (such as heart valves) with their care team, allowing their baby to leave a lasting legacy ^[8].

Experimental Intervention: The RAFT Trial

For some families, an experimental approach called the RAFT (Renal Anhydramnios Fetal Therapy) trial may be an option. This NIH-funded study investigates whether serial amnioinfusions can help the baby’s lungs develop enough to survive after birth ^[9].

How it works:
Doctors use a needle to periodically “refill” the amniotic fluid around the baby during pregnancy ^[10]. The hope is that this fluid will allow the lungs to grow, potentially buying time for the baby to reach birth and begin life-sustaining treatments like peritoneal dialysis (a way to filter the blood when kidneys don’t work) ^[11].

Important Considerations:

• Risks: These procedures carry significant risks to both mother and baby, including infection, preterm labor, or the premature breaking of the water (PPROM) ^[12][13].
• Long-term Care: If successful, the baby will still be born with end-stage renal disease and will require intensive medical care, daily dialysis, and eventually a kidney transplant ^[14].
• Outcomes: While amnioinfusions may improve survival in the short term, long-term outcomes are still being studied and are not guaranteed ^[15].

Choosing between these paths is a deeply personal journey. Your medical team is there to provide the data, but you are the expert on what is best for your child and your family.