Absent kidney (unilateral renal agenesis)

Most people are born with two kidneys, but some people only have one and can go on to lead a normal life.

The scan you have had has shown that your baby has probably just one kidney, so the other has not developed correctly while growing in the womb.

Usually the reason is unknown.

Where are the kidneys?

The kidneys are bean shaped organs located at the bottom of the rib cage at the back of the body.


What do the kidneys do?

Some functions are:

  • Remove waste products
  • Maintains normal blood pressure
  • Filters the blood and forms the urine

The urine flows from the kidneys through the ureters to the bladder and then from here passes through the urethra to the outside of the body.

What happens during the pregnancy?

You will initially discuss your scan findings with the Fetal Medicine Midwife or appropriately trained professional.

You will be referred to the Fetal Medicine Clinic for a scan and to discuss further with the Consultant Obstetrician.

You may need more scans during your pregnancy to check how your baby is growing and to assess the health of the kidney and urinary system.

Amniotic fluid (water)will be measured to ensure it is at a normal level.

The amniotic fluid is made up of urine which is produced by the kidney.

Your Consultant will refer you to a neonatologist (the doctor who treats babies) during the pregnancy so they are aware of your baby’s condition before your delivery.

After Delivery

Baby will receive a full physical check on the postnatal ward prior to your discharge home.

Your baby will have a renal (kidney) scan but usually this is performed after discharge from hospital.

An appointment to see a Paediatric Nephrologist will be arranged and then regular check ups to ensure baby and the kidney is healthy.

Future Outlook

Many children with an absent kidney will not have long term problems and be able to do all that other children do.

Some may be at a slightly higher chance of urinary infections.

Useful Websites

ARC (Antenatal Results and Choices) Offer information and support to parents who are making decisions before, during and after tests in pregnancy

Website:  https://www.arc-uk.org/

Tel no: 084507722990 

INFOKID (information for parents and carers about children’s kidney conditions)

Website: https://www.infokid.org.uk/

Improving the physical and emotional health and wellbeing of expectant mothers, infants, children and young people throughout Aneurin Bevan University Health Board Area.

(N.B: The Family and Therapies team at ABUHB is NOT responsible for the content on the webpage links that we refer to in our resource sections and linked information to external sites. All information was accurate and appropriate at the time the webpage was created.)

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