What are Cloacal Malformations?

A cloaca is a malformation in females where the rectum, vagina, and urinary tract are fused together, creating a single common channel. In normal anatomy, these openings are separate. Cloacas affect one of every 20,000 to 25,000 newborn girls. They are most often diagnosed just after the baby is born, but occasionally there are clues on the prenatal ultra sound. 

Urinary System and Gynecologic Organs

About half of patients with cloacas also have a defect affecting their urinary and gynecologic organs. Some children may have only one kidney, or they have urine that backs up into the kidneys (vesicoureteral reflux) or enlargement of the kidney drainage system (hydronephrosis).  

Another potential problem is hydrocolpos. This is a condition where fluid collects within the vagina and uterus that may press on the base of the bladder neck, causing a blockage of the ureters, which does not allow them to drain into the bladder.

About half of girls with cloaca will have problems with gynecologic organs that may affect these organs’ functions later in life, including the ability to give birth. 

Spinal and Sacral Defects

The sacrum, or small bones found in the lower back, can often be affected. Sometimes one or more of the bones may be missing. More often though, the sacrum may be smaller and not formed correctly. In some cases, the spinal cord may be incorrectly positioned within the bones of the spinal column, and this condition called tethered cord may need repair. 

Associated Conditions

Identifying other abnormalities or defects is the main priority in confirming the diagnosis and treatment of cloacas. These abnormalities typically involve the urinary system, the gynecologic organs, such as the vagina and uterus, and the lower back and spinal column.

How are Cloacal Malformations Diagnosed?

The diagnosis and treatment of cloacal malformations requires a collaborative effort by experienced pediatric general surgeons, pediatric urologists, pediatric gynecologists and other specialists.

The initial evaluation and immediate treatment will:

  • identify all the possible defects related to this condition 
  • provide drainage of the urinary tract, usually the decompression of the gynocologic system connected to it
  • divert the bowel, to allow waste to exit the body, using a colostomy (an opening of the bowel through the abdomen (stomach area)). 

Diagnostic tests in the newborn period include: ultrasonography of the kidneys, bladder and other pelvic organs, x-rays of the spine and sacrum, and spinal ultrasound.

Once the child is stable and able to eliminate urine and waste from her body, the surgical team will determine the appropriate course of treatment. Cloaca anatomy can vary widely, and the complexity of the surgical reconstruction also varies. 

Types of Treatment

While the initial goal is to stabilize the child and relieve blockages in the urinary and intestinal tract, the long-range goals are directed at restoring anatomy and function. 

Diagnostic tests of the cloaca help determine the length of the common channel as well as other important aspects that determine the best way to correct the malformation.

Patients usually fall into one of two groups, with each requiring a different treatment approach. The first group involves girls that are born with a common channel shorter than 3 centimeters, or smaller than one inch, For most of these patients, the cloaca can be repaired without the need for an incision through the abdominal (stomach) area. 

The second group includes patients with longer common channels. These patients usually need a laparotomy, or incision through the abdominal area. Decisions must also be made about urinary and vaginal reconstruction or replacement. These types of corrective surgery are best handled in centers with a team who specializes in the repair of these defects, and have collaboration between pediatric colorectal surgery, urology and gynecology. 


The main goal is for the child to gain urinary and bowel control, and to be able to function sexually later in her life. For additional information about the prognosis for cloaca patients, click here