Reimbursement Advisor

ICD-10-CM documentation 
and coding for obstetric procedures

Author and Disclosure Information

With the new system set to take effect in less than a month, here’s what you need to know about key changes to obstetric coding

In this Article

  • How to do a gap analysis
  • Highlights of OB coding
  • Condition-specific coding notations



The countdown is on for the big 
coding switch. Last month I wrote about changes in International 
Classification of Diseases, 10th Revision, 
Clinical Modification (ICD-10-CM) codes that will occur in relation to gynecologic services, but now it’s time to tackle obstetric services. For obstetricians, the changes will be all about definitions. And documentation of obstetric conditions will be more complicated due to several factors, including the need to report trimester information and gestational age, use of a placeholder code, more complex guidelines for certain conditions, chorionicity for multiple gestations, and use of a 7th digit to identify the fetus with a problem.

No one is expecting clinicians to instantly be fluent in code-speak, but in order for the most specific diagnoses to be reported, the clinical documentation must be spot on. Think of it this way: ICD-10-CM is not requiring you to document more, it’s requiring you to document more precisely.

How to get started

Figuring out where you are now goes a long way toward knowing where you need to be when the calendar changes to October 1—and the best way to do it is to perform a gap 
analysis. This analysis can be carried out by the clinician or a qualified practice staff person.

To begin, run a report of the distinct obstetric codes you have billed in 2015 by frequency. Then sort them in numeric order so that each individual code category is captured for all of the 5th digits (and the code then will be counted as a single code). Finally, review 5 medical records for each of the top 10 reported diagnosis categories and determine whether you could have reported a more specific ICD-10-CM code.

The information you gain will go a long way toward identifying potential weaknesses in the documentation, or, if you are currently using an electronic health record (EHR) to look up a code, it will point up any weak points in searching for the right code, based on your specific documentation at the encounter. Remember, practice makes perfect…eventually.

Well-trained staff can help

Not only must you, the clinician, learn about the part your clinical documentation will play in providing the most specific information that will lead to a very specific code, but your coding and billing staff will need training as well. They are the ones who should be checking your claims for accuracy from October 1
forward, as they will know the basic rules about which codes can be billed together, code order, place codes, and so on. In other words, while you as a clinician should be responsible for picking the more specific code in ICD-10-CM, your staff is your backup 
when you don’t.

Feedback from your staff on how the claims are being processed and, perhaps, the overuse of unspecified codes will keep you moving toward the goal of complete and precise clinical documentation and the reporting of diagnoses at the highest level possible given the documentation.

Highlights of ICD-10-CM obstetric coding

Given the complexity of obstetric coding, this article deals only with the most important changes. It will be up to each clinician to learn the rules that surround the diagnostic codes that you report most frequently. Here again, a trained staff can help by preparing specific coding tools for the most frequently used diagnoses, including notes about what must be in the record to report the most specific code.

Trimester, gestational age, 
and timing definitions

The majority of obstetric complication codes (these are the codes that start with the letter “O”) and the “Z” codes for supervision of a normal pregnancy require trimester information to be valid. In the outpatient setting, the trimester will be based on the gestational age at the date of the encounter. For inpatient admissions, the trimester will be based on the age at the time of admission; if the patient is hospitalized over more than one trimester, it is the admission trimester that continues to be recorded, not the discharge trimester.

Although there are codes that indicate an unspecified trimester, they should be reported rarely if this information is, in fact, available. Trimesters are defined as:

  • first: less than 14 weeks, 0 days
  • second: 14 weeks, 0 days to less than 
28 weeks, 0 days
  • third: 28 weeks, 0 days until delivery.

Examples of trimester codes include:

  • O25.11Malnutrition in pregnancy, first trimester
  • O14.02 Mild to moderate preeclampsia, second trimester
  • O24.013 Preexisting diabetes mellitus, 
type 1, in pregnancy, third trimester.

However, definitions in ICD-10-CM go beyond this, and these definitions will have to be taken into account to provide sufficient documentation to report the condition. In ICD-9-CM, a missed abortion and early hemorrhage in pregnancy occurred prior to 
22 completed weeks, but in ICD-10-CM that definition changes to prior to 20 completed weeks.


Next Article:

ObGyn salaries continue gradual improvement

Related Articles