2021 ICD-10-CM Code O99.412

Diseases of the circulatory system complicating pregnancy, second trimester

Version 2021
Billable Code
Maternity Diagnoses
Diagnoses For Females Only
Second Trimester (14 to 27 Weeks)
MS-DRG Mapping

Valid for Submission

O99.412 is a billable diagnosis code used to specify a medical diagnosis of diseases of the circulatory system complicating pregnancy, second trimester. The code O99.412 is valid during the fiscal year 2021 from October 01, 2020 through September 30, 2021 for the submission of HIPAA-covered transactions.

The code O99.412 is applicable to female patients aged 12 through 55 years inclusive. It is clinically and virtually impossible to use this code on a non-female patient outside the stated age range.

ICD-10:O99.412
Short Description:Diseases of the circ sys comp pregnancy, second trimester
Long Description:Diseases of the circulatory system complicating pregnancy, second trimester

Code Classification

Code Edits

The Medicare Code Editor (MCE) detects and reports errors in the coding of claims data. The following ICD-10 Code Edits are applicable to this code:

Convert O99.412 to ICD-9 Code

The General Equivalency Mapping (GEM) crosswalk indicates an approximate mapping between the ICD-10 code O99.412 its ICD-9 equivalent. The approximate mapping means there is not an exact match between the ICD-10 code and the ICD-9 code and the mapped code is not a precise representation of the original code.

Information for Patients


Health Problems in Pregnancy

Every pregnancy has some risk of problems. You may have problems because of a health condition you had before you got pregnant. You could also develop a condition during pregnancy. Other causes of problems during pregnancy can include being pregnant with more than one baby, a health problem in a previous pregnancy, substance abuse during pregnancy, or being over age 35. Any of these can affect your health, the health of your baby, or both.

If you have a chronic condition, you should talk to your health care provider about how to minimize your risk before you get pregnant. Once you are pregnant, you may need a health care team to monitor your pregnancy. Some common conditions that can complicate a pregnancy include

Other conditions that can make pregnancy risky can happen while you are pregnant - for example, gestational diabetes and Rh incompatibility. Good prenatal care can help detect and treat them.

Some discomforts, like nausea, back pain, and fatigue, are common during pregnancy. Sometimes it is hard to know what is normal. Call your health care provider if something is bothering or worrying you.


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Heart Diseases

Also called: Cardiac diseases

If you're like most people, you think that heart disease is a problem for others. But heart disease is the number one killer in the U.S. It is also a major cause of disability. There are many different forms of heart disease. The most common cause of heart disease is narrowing or blockage of the coronary arteries, the blood vessels that supply blood to the heart itself. This is called coronary artery disease and happens slowly over time. It's the major reason people have heart attacks.

Other kinds of heart problems may happen to the valves in the heart, or the heart may not pump well and cause heart failure. Some people are born with heart disease.

You can help reduce your risk of heart disease by taking steps to control factors that put you at greater risk:

NIH: National Heart, Lung, and Blood Institute


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Vascular Diseases

What are vascular diseases?

Your vascular system is your body's network of blood vessels. It includes your

Vascular diseases are conditions which affect your vascular system. They are common and can be serious. Some types include

What causes vascular diseases?

The causes of vascular diseases depend on the specific disease. These causes include

Sometimes the cause is unknown.

Who is at risk for vascular diseases?

The risk factors for vascular diseases can vary, depending on the specific disease. But some of the more common risk factors include

What are the symptoms of vascular diseases?

The symptoms for each disease are different.

How are vascular diseases diagnosed?

To make a diagnosis, your health care provider will do a physical exam and ask about your symptoms and medical history. You may have imaging tests and/or blood tests.

How are vascular diseases treated?

Which treatment you get depends on which vascular disease you have and how severe it is. Types of treatments for vascular diseases include

Can vascular diseases be prevented?

There are steps you can take to help prevent vascular diseases:


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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)