The exact causes of prune belly syndrome are unknown. The condition affects mostly boys.

While in the womb (uterus), the developing baby's abdomen swells with fluid. Often, the cause is a problem in the urinary tract. The fluid disappears after birth, leading to a wrinkled abdomen that looks like a prune. This appearance is more noticeable due to the lack of abdominal muscles.

Weak abdominal muscles can cause:

• Constipation
• Delay in sitting and walking
• Difficulties coughing

Urinary tract problems can cause difficulty urinating.

A woman who is pregnant with a baby who has prune belly syndrome may not have enough amniotic fluid (the fluid that surrounds the fetus). This can cause the infant to have lung problems from being compressed in the womb.

An ultrasound done during pregnancy may show that the baby has a swollen bladder or enlarged kidney.

In some cases, a pregnancy ultrasound may also help determine if the baby has:

• Heart problems
• Abnormal bones or muscles
• Stomach and intestinal problems
• Underdeveloped lungs

The following tests may be performed on the baby after birth to diagnose the condition:

• Blood tests
• Intravenous pyelogram (IVP)
• Ultrasound
• Voiding cystourethrogram (VCUG)
• X-ray
• CT scan

Early surgery is recommended to fix weak abdominal muscles, urinary tract problems, and undescended testicles.

The baby may be given antibiotics to treat or help prevent urinary tract infections.

More information and support for people with prune belly syndrome and their families can be found at:

• Prune Belly Syndrome Network -- prunebelly.org

Prune belly syndrome is a serious and often life-threatening problem.

Many infants with this condition are either stillborn or die within the first few weeks of life. The cause of death is from severe lung or kidney problems, or from a combination of birth problems.

Some newborns survive and can develop normally. Others continue to have many medical and developmental problems.

Complications depend on the related problems. The most common are:

• Constipation
• Bone deformities (clubfoot, dislocated hip, missing limb, finger, or toe, funnel chest)
• Disease of the urinary tract (may need dialysis and a kidney transplant)

Undescended testicles can lead to infertility or cancer.

Prune belly syndrome is usually diagnosed before birth or when the baby is born.

If you have a child with diagnosed prune belly syndrome, contact your health care provider at the first sign of a urinary tract infection or other urinary symptoms.

If a pregnancy ultrasound shows that your baby has a swollen bladder or enlarged kidneys, talk to a specialist in high-risk pregnancy or perinatology.

There is no known way to prevent this condition. If the baby is diagnosed with a urinary tract obstruction before birth, in rare cases, surgery during the pregnancy may help prevent the problem from progressing to prune belly syndrome.

Eagle-Barrett syndrome; Triad syndrome

Denes FT, Lopes RI. Prune-belly syndrome. In: Partin AW, Dmochowski RR, Kavoussi LR, Peters CA, eds. Campbell-Walsh-Wein Urology. 12th ed. Philadelphia, PA: Elsevier; 2021:chap 32.

Di Carlo HN, Crigger CB. Obstruction of the urinary tract. In: Kliegman RM, St. Geme JW, Blum NJ, et al, eds. Nelson Textbook of Pediatrics. 22nd ed. Philadelphia, PA: Elsevier; 2025:chap 577.

Rowe CK, Merguerian PA. Developmental abnormalities of the genitourinary system. In: Gleason CA, Sawyer T, eds. Avery's Diseases of the Newborn. 11th ed. Philadelphia, PA: Elsevier; 2024:chap 76.

Updated by: Anna C. Edens Hurst, MD, MS, Associate Professor in Medical Genetics, The University of Alabama at Birmingham, Birmingham, AL. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.