Bladder exstrophy (EK-stroh-fee) is a rare birth defect in which the bladder develops outside the fetus. The condition is more common in males than in females. The exposed bladder and urethra — the tube that expels urine — result in the bladder being unable to store urine.
Bladder exstrophy is the most common of a larger group of birth defects called the bladder exstrophy-epispadias (EK-stroh-fee-ep-ih-SPAY-dee-us) complex (BEEC). Defects resulting from this complex range from mild to severe. Bladder exstrophy itself also has a range of severity and, in addition to the abnormalities in the bladder, genitals and pelvic bones, may include defects in the intestines and reproductive organs.
Often doctors will identify bladder exstrophy on an ultrasound during pregnancy. Sometimes, though, the defect isn't visible until after the baby is born.
Surgeons treat bladder exstrophy after birth. Surgical repair is usually done at age 3 months or later. Sometimes two or more procedures are needed. Some children require additional surgery around age 4.
With surgery, and sometimes with medication, many children achieve bladder control (continence).
Bladder exstrophy is the most common of a larger group of birth defects called the bladder exstrophy-epispadias complex (BEEC). As the fetus grows, a structure called the cloaca (klo-AY-kuh) — where reproductive, urinary and digestive openings all come together — does not develop properly. The resulting defects can range greatly in severity depending on the age of the fetus when the developmental error occurs. If your child has BEEC, he or she will have one of the following:
- Epispadias. This is the least severe form of BEEC, in which the tube to expel urine (urethra) does not fully develop.
Bladder exstrophy. This is the most common form of BEEC. Bladder exstrophy means that the bladder is formed on the outside of the body and is turned inside out. Usually bladder exstrophy will involve organs of the urinary tract, as well as the digestive and reproductive systems. The condition can include specific defects of the abdominal wall, bladder, genitals, pelvic bones, final section of the large intestine (rectum) and opening at the end of the rectum (anus).
Children with bladder exstrophy will also have a condition called vesicoureteral reflux, in which urine flows the wrong way — from the bladder back up into the tubes that connect to the kidneys (ureters). Children with bladder exstrophy also have epispadias.
These defects are treated through surgical procedures that repair the affected organs, muscles and bones.
Cloacal exstrophy. Cloacal exstrophy (KLOA-kul EK-stroh-fee) is the most serious form of BEEC, in which the rectum, bladder and genitals did not fully separate as the fetus developed. These organs may not be correctly formed. The pelvic bones are more severely affected as well. The backbone and spinal cord may be affected, as well as the kidneys.
Children born with protruding abdominal organs (omphalocele) likely have cloacal exstrophy. However, an omphalocele (OM-fuh-loh-seel) may occasionally be associated with bladder exstrophy as well. Most children with cloacal exstrophy have spinal abnormalities, including spina bifida.
Doctors aren't sure what causes bladder exstrophy. As with similar problems, it appears to result from a combination of genetic and environmental risk factors.
- Genetic factors. Recent studies indicate that the master control gene ISL1 is probably a susceptibility gene for bladder exstrophy. A susceptibility gene is one that is likely the cause of a specific disease or disorder. This gene is also important in regulating urinary tract development.
- Environmental factors. Some research suggests associations with the age of the mother, assisted reproduction, use of the hormone progesterone during pregnancy and smoking during pregnancy, but no cause and effect has been determined.
Factors that increase the risk of bladder exstrophy include:
- Family history. Firstborn children, children of a parent with bladder exstrophy or siblings of a child with bladder exstrophy have an increased chance of being born with the condition.
- Race. Bladder exstrophy is more common in whites than in other races.
- Sex. More males than females are born with bladder exstrophy.
If not treated, children with bladder exstrophy will have an inability to hold urine (urinary incontinence) and an increased risk of bladder cancer. They're also at risk of sexual dysfunction.
Surgical treatment can reduce complications, depending on the severity of defects. Many children who have surgical repair are able to hold urine (continent). Young children with bladder exstrophy may walk with their legs turned somewhat outward, due to the separation of their pelvic bones.
People born with bladder exstrophy can go on to have normal sexual function, including the ability to have children. However, pregnancy will be high risk for both mother and baby. It's possible for pregnant women with bladder exstrophy to choose a vaginal birth, although it may be complicated by the condition of her cervical tissue. A planned cesarean section is likely to be the preferable option.