ICD-10-PCS 7th Character Extensions and Obstetric Coding

Posted on 06.29.2016

Dear Instructor,
I am having some trouble understanding how to apply 7th characters extensions where a mother is being treated due to a problem with the fetus. Do you have any advice on how to assign these characters to OB cases?
Anxious in Akron

Dear Anxious,
Never fear…assigning 7th character extensions to codes that report maternal care related to a complication with the fetus is easy once you understand a few points as outlined below.

• A 7th character extension is needed for all codes from categories: O31, O32, O33.3-O33.6, O35, O36, O40, O41, O60.1, O60.2, O64 and O69.

If the code you are assigning comes from one of these categories, you know you will need to be on your toes and make sure a 7th character is assigned.

• The 7th character extension identifies the fetus involved in the complication.

• The character options available include the numbers 0 through 5 and the number 9.

o A 7th character of “0” is used for single gestations and multiple gestations where the fetus is unspecified or cannot be clinically determined.

o The 7th characters of 1 through 5 are used in cases of multiple gestations, comprised of up to 5 fetuses, to identify the fetus to which the code applies. A 7th character of “9” is assigned to any fetus beyond fetus 5.

• Do not get confused and assign a character value of “1”, for fetus 1, for a single gestation pregnancy. The designation of “fetus 1” tells you this is a multiple gestation pregnancy. “0” (zero) means the idea of “fetus identification” is not applicable because it’s not a multiple gestation.

• Remember, using a number from 1 to 9 to identify a fetus is only applicable to multiple gestations and clinical documentation in the record is what is used to identify fetus 1, fetus 2, and so on.

Let’s take a look at an example of a common obstetric coding scenario, a breech presentation of a single fetus.

The correct code to assign for this scenario is O32.1XX0.


The category of O32 indicates maternal care for mal-presentation of fetus. The 4th character of “1” specifies the etiology, which in this case, would be the breech presentation.  The X in the 5th and 6th character positions are placeholders used solely to maintain the 7th character position.  The 7th character of “0” (zero) indicates a single fetus is involved.

If coding a case involving a twin pregnancy where both babies are in a breech position, two codes would be required. The codes used would be O32.1xx1 (Fetus 1 is breech) and O32.1xx2 (Fetus 2 is also breech).

To recap: Anytime a pregnant woman in being treated due to a complication with a fetus a 7th character extension will be assigned to the code for the complication. The 7th character will be a number 0 to 5 or the number 9. The 7th character of 0 is used for single gestations or when the specific fetus involved cannot be determined. For multiple gestation pregnancies, the number 9 is assigned to any fetus beyond the 5th and finally, 7th character extensions are assigned based on the documentation in the record of fetus 1, fetus 2 and so forth.

Happy Coding!


Your Instructor