2021 ICD-10-CM Code O10.91

Unspecified pre-existing hypertension complicating pregnancy

Version 2021
Non-Billable Code
Unspecified Code

Not Valid for Submission

O10.91 is a "header" nonspecific and non-billable diagnosis code code, consider using a code with a higher level of specificity for a diagnosis of unspecified pre-existing hypertension complicating pregnancy. The code is NOT valid for the year 2021 for the submission of HIPAA-covered transactions. Category or Header define the heading of a category of codes that may be further subdivided by the use of 4th, 5th, 6th or 7th characters.

Unspecified diagnosis codes like O10.91 are acceptable when clinical information is unknown or not available about a particular condition. Although a more specific code is preferable, unspecified codes should be used when such codes most accurately reflect what is known about a patient's condition. Specific diagnosis codes should not be used if not supported by the patient's medical record.

ICD-10:O10.91
Short Description:Unspecified pre-existing hypertension complicating pregnancy
Long Description:Unspecified pre-existing hypertension complicating pregnancy

Code Classification

Specific Coding for Unspecified pre-existing hypertension complicating pregnancy

Header codes like O10.91 require more digits to indicate the appropriate level of specificity. Consider using any of the following ICD-10 codes with a higher level of specificity when coding for unspecified pre-existing hypertension complicating pregnancy:

Index to Diseases and Injuries

The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for the code O10.91 are found in the index:

Information for Patients


High Blood Pressure in Pregnancy

What is high blood pressure in pregnancy?

Blood pressure is the force of your blood pushing against the walls of your arteries as your heart pumps blood. High blood pressure, or hypertension, is when this force against your artery walls is too high. There are different types of high blood pressure in pregnancy:

What causes preeclampsia?

The cause of preeclampsia is not known.

Who is at risk for preeclampsia?

You are at higher risk of preeclampsia if you

What problems can preeclampsia cause?

Preeclampsia can cause

What are the symptoms of preeclampsia?

Possible symptoms of preeclampsia include


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Code History

  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016 (First year ICD-10-CM implemented into the HIPAA code set)