Culdocentesis is a procedure to examine any abnormal fluid in the pouch-like space just behind the vagina

Culdocentesis is a procedure to examine any abnormal fluid in the pouch-like space just behind the vagina (cul-de-sac or pouch of Douglas).

In the culdocentesis procedure:

The physician will first perform a pelvic examination
Lying in the same position with your head elevated to 60 degrees, the physician inserts a lubricated tool, known as a speculum, to examine the cervix (the neck of the womb)
Next, the physician cleanses the vagina and cervix with antiseptic and applies 2% Lidocaine gel to the vaginal lip or cervical lip
Using a tool called a tenaculum, the physician grasps the cervix and lifts to expose the vaginal fold (posterior fornix)
Next, the physician injects normal saline into the cul-de-sac and empties it. After injecting the normal saline, the physician pulls back the syringe plunger while slowly withdrawing the needle
The fluid collected is sent for analysis
If there’s no fluid collected in the first attempt, the physician withdraws the needle and then reintroduces it

Depending on the type of fluid withdrawn, the result interpretation involves:

A small amount of clear fluid is normal, but the chances of ovarian cyst, unruptured ectopic pregnancy (pregnancy at a site other than the womb), tubal infection, or other disorders can be a possibility
No fluid in the cul-de-sac can also be a normal finding
Nonclotting blood indicates active bleeding from a ruptured ectopic pregnancy
Clotting blood indicates blood from the vein or artery during an aspiration
The presence of pus indicates an infection, such as pelvic inflammatory disease

To prepare for culdocentesis, you have to follow these instructions:

Detail your medical and medication history to your physician
Undergo a pelvic examination for the physician to identify the abnormality of the cul-de-sac
Understand each step of culdocentesis to know what to expect from the procedure
Give your informed consent after understanding the procedure thoroughly
You may need to walk or sit upright for 10 to 15 minutes to allow the fluid to pool into the cul-de-sac
Inform about any drug allergies or substance allergy to your physician
Quit cigarette smoking and other nicotine products before the procedure
Avoid alcohol for a few days before the surgery
You may have to undergo specific tests before the procedure, which include:
- Blood tests and urine analysis
- Computed tomography (CT) scan
- Ultrasound
- X-ray of the lower abdomen

After a culdocentesis procedure: