Location, Location, Location!

Interstitial. Cesarean scar. Cervical. Cornual. Four ectopic pregnancy locations that will have their own coding pathways when the FY 2027 ICD-10-CM code updates take effect on October 1, 2026. The terms may sound similar, and at times they are used inconsistently in the medical record, but the new codes make the exact site of the ectopic pregnancy an important part of code assignment. In this segment of “In the kNOW”, we’ll review what is changing and the documentation coding professionals will need.

Let’s begin with the basic concept. An ectopic pregnancy occurs when a fertilized egg implants in an abnormal location that cannot support the pregnancy. Although many ectopic pregnancies are tubal, implantation can occur in other locations. The 2027 code update recognizes several of these locations more specifically and provides separate code choices based on whether an intrauterine pregnancy is also present.

Currently, cervical pregnancy and cornual pregnancy are included under O00.8, Other ectopic pregnancy. Effective October 1, those inclusion terms are deleted from O00.8 because separate categories are being created. Interstitial ectopic pregnancy will be further classified under O00.1, Tubal pregnancy, while cesarean scar, cervical, and cornual ectopic pregnancies receive their own subcategories.

The new code structure includes the following: 

• O00.12 Interstitial ectopic pregnancy without intrauterine pregnancy:
  O00.121 right
  O00.122 left
  O00.129 unspecified

• O00.13 Interstitial ectopic pregnancy with intrauterine pregnancy:
  O00.131 right
  O00.132 left
  O00.139 unspecified

• O00.3 Cesarean scar ectopic pregnancy:
  O00.31 without intrauterine pregnancy
  O00.32 with intrauterine pregnancy

• O00.4 Cervical ectopic pregnancy:
  O00.41 without intrauterine pregnancy
  O00.42 with intrauterine pregnancy

• O00.51 Cornual ectopic pregnancy without intrauterine pregnancy:
  O00.511 right
  O00.512 left
  O00.519 unspecified

• O00.51 Cornual ectopic pregnancy with intrauterine pregnancy: 
  O00.521 right
  O00.522 left
  O00.529 unspecified

The expanded choices mean the documentation must do more than state “ectopic pregnancy.” Coding professionals should look for the exact location, whether the condition is right-sided or left-sided when laterality is built into the code, and whether an intrauterine pregnancy is also present. The presence or absence of an intrauterine pregnancy changes the code assignment in each of the new code families.

It is also important not to assume that interstitial and cornual mean the same thing. The FY2027 classification provides different code paths for these diagnoses. If both terms appear in the record or the documentation is unclear, the coding professional should not select a code based on personal interpretation. The provider should be queried so that the final diagnosis identifies the specific condition.

To apply the change, review this scenario. A patient at eight weeks’ gestation presents with pelvic pain. The emergency department note documents a suspected right “cornual/interstitial” ectopic pregnancy. The ultrasound report describes a right interstitial pregnancy, while the operative report uses the term cornual pregnancy. No intrauterine pregnancy is identified. Because the new code set treats interstitial and cornual ectopic pregnancy as separate diagnoses, the coding professional should query the provider rather than choose between the two terms. The provider clarifies that the final diagnosis is a right interstitial ectopic pregnancy without an intrauterine pregnancy. The proper code assignment is O00.121. If the provider had clarified a right cornual ectopic pregnancy, the correct code would be O00.511.

Two additional points. First, the FY 2027 codes apply to patient encounters and discharges occurring on or after October 1, 2026. Encounters before that date must be coded using the code set in effect on the date of service or discharge. Second, several of the new entries, such as O00.12, O00.13, and O00.5, are subcategories rather than complete reportable codes. Coding professionals must continue through the Tabular List and assign the code to the highest level of specificity supported by the documentation.

Organizations should make sure encoder updates, coding references, clinical documentation education, and internal audit tools are ready before October 1. These changes provide more precise reporting, but the accuracy of the final code will still depend on clear provider documentation of location, laterality, and the presence or absence of an intrauterine pregnancy. 

Now you are In the kNOW!!

 

About the Author

Dianna Foley, RHIA, CCS, CDIP, CHPS, has 25 years of HIM experience. She earned her bachelor’s degree from the University of Cincinnati and holds RHIA, CHPS, CDIP, and CCS certifications from AHIMA. Dianna’s an AHIMA-approved ICD-10-CM/PCS trainer, an AHIMA-published author, a participant in AHIMA credential item writing and exam development, and served on the AHIMA Nominating Committee. Dianna has held various HIM positions and is now an independent coding consultant. She previously served as a program director for Medical Coding and HIT. She presents on coding topics at the national, state, and regional levels and serves as OHIMA’s Education Coordinator.