2025 ICD-10-CM Diagnosis Code O11

Pre-existing hypertension with pre-eclampsia

ICD-10-CM Code:: O11
ICD-10 Code for:: Pre-existing hypertension with pre-eclampsia
Is Billable?: Not Valid for Submission
Code Navigator:

O11 is a non-specific and non-billable diagnosis code code, consider using a code with a higher level of specificity for a diagnosis of pre-existing hypertension with pre-eclampsia. The code is not specific and is NOT valid for the year 2025 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.

Table of Contents

Code Information
Specific Coding
Tabular List of Diseases and Injuries
Patient Education
Other Codes Used Similar Conditions
Code History

Specific Coding Applicable to Pre-existing hypertension with pre-eclampsia

Non-specific codes like O11 require more digits to indicate the appropriate level of specificity. Consider using any of the following ICD-10-CM codes with a higher level of specificity when coding for pre-existing hypertension with pre-eclampsia:

Use O11.1 for Pre-existing hypertension with pre-eclampsia, first trimester - BILLABLE CODE
Use O11.2 for Pre-existing hypertension with pre-eclampsia, second trimester - BILLABLE CODE
Use O11.3 for Pre-existing hypertension with pre-eclampsia, third trimester - BILLABLE CODE
Use O11.4 for Pre-existing hypertension with pre-eclampsia, complicating childbirth - BILLABLE CODE
Use O11.5 for Pre-existing hypertension with pre-eclampsia, complicating the puerperium - BILLABLE CODE
Use O11.9 for Pre-existing hypertension with pre-eclampsia, unspecified trimester - BILLABLE CODE

Code Classification

Pregnancy, childbirth and the puerperium
O00-O9A
- Edema, proteinuria and hypertensive disorders in pregnancy, childbirth and the puerperium
  O10-O16
  - Pre-existing hypertension with pre-eclampsia
    O11

Tabular List of Diseases and Injuries

The following annotation back-references are applicable to this diagnosis code. The Tabular List of Diseases and Injuries is a list of ICD-10-CM codes, organized "head to toe" into chapters and sections with coding notes and guidance for inclusions, exclusions, descriptions and more.

Includes

conditions in O10
pre-eclampsia superimposed pre-existing hypertension

Use Additional Code

code from O10

Patient Education

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. Your arteries are blood vessels that carry blood from your heart to other parts of your body. High blood pressure, or hypertension, is blood pressure that is higher than normal. Having high blood pressure can put you at risk for other health problems, such as heart disease, heart attack, and stroke.

During pregnancy, high blood pressure can cause problems for you and your baby. To keep you and your baby healthy, it's important to get treatment for high blood pressure before, during, and after pregnancy.

What are the types of high blood pressure in pregnancy?

There are different types of high blood pressure in pregnancy:

Gestational hypertension is high blood pressure that you develop while you are pregnant. It starts after you are 20 weeks pregnant. You usually don't have any other symptoms. In many cases, it does not harm you or your baby, and it goes away within 12 weeks after childbirth. But it does raise your risk of high blood pressure in the future. If it becomes severe, it can lead to a preterm birth or your baby having a low birth weight. Some women with gestational hypertension do go on to develop preeclampsia, a more serious type of high blood pressure in pregnancy.
Chronic hypertension is high blood pressure that starts before the 20th week of pregnancy or before you became pregnant. Some people may have had it long before becoming pregnant but didn't know it until they got their blood pressure checked at their prenatal visit. Sometimes chronic hypertension can also lead to preeclampsia.
Preeclampsia is a sudden increase in blood pressure after the 20th week of pregnancy. It usually happens in the last trimester. Preeclampsia also often includes signs of damage to some of your organs, such as your liver or kidneys. The signs may include protein in the urine (pee) and very high blood pressure. Preeclampsia can be serious or even life-threatening for both you and your baby.
- If preeclampsia becomes severe enough to affect your brain function and causes seizures or a coma, it is called eclampsia.
- In rare cases, preeclampsia symptoms may not start until after delivery. This is called postpartum preeclampsia. If this type of preeclampsia becomes more severe and causes a seizure, it is known as postpartum eclampsia.
- When a person with preeclampsia or eclampsia has damage to the liver and blood cells, it's called HELLP syndrome. It is rare, but very serious.

Who is more likely to develop high blood pressure in pregnancy?

You are more likely to develop high blood pressure in pregnancy if you:

Had chronic high blood pressure or chronic kidney disease before pregnancy
Had high blood pressure or preeclampsia in a previous pregnancy
Have obesity
Are under age 20 or over age 40
Are pregnant with more than one baby
Are African American
Have a family history of high blood pressure in pregnancy
Have certain health conditions, such as diabetes or lupus

What are the symptoms of high blood pressure in pregnancy?

High blood pressure usually has no symptoms. People usually find out they have high blood pressure when their health care provider measures their blood pressure.

Preeclampsia can cause other symptoms, including:

Too much protein in your urine (called proteinuria).
Swelling (edema) in your face and hands. Your feet may also swell, but many women have swollen feet during pregnancy. So swollen feet by themselves may not be a sign of a problem.
A headache that does not go away.
Vision problems, including blurred vision or seeing spots.
Pain in your upper right abdomen (belly).
Trouble breathing.

Eclampsia can also cause seizures, nausea and/or vomiting, and low urine output.

If you go on to develop HELLP syndrome, you may also have bleeding or bruising easily, extreme fatigue, and liver failure.

What problems can high blood pressure in pregnancy cause?

High blood pressure in pregnancy can lead to complications such as:

Placental abruption, where the placenta (the organ that brings oxygen and nutrients to the baby) separates from the uterus (the place where a baby grows during pregnancy)
Poor fetal growth, caused by a lack of nutrients and oxygen
Preterm birth
Your baby having a low birth weight
Damage to your kidneys, liver, brain, and other organ and blood systems
A higher risk of heart disease for you

How is high blood pressure in pregnancy diagnosed?

Your provider will check your blood pressure and urine at each prenatal visit. If your blood pressure reading is high (140/90 or higher), especially after the 20th week of pregnancy, your provider will likely want to order some tests. These may include blood tests and other lab tests, such as a test to look for extra protein in your urine.

What are the treatments for high blood pressure in pregnancy?

If you have high blood pressure, you and your baby will be closely monitored to lower the chance of complications. You may need to:

Check your blood pressure at home.
Keep track of how many times you feel the baby kicking each day.
Adjust your physical activity. Talk to your provider about what level of physical activity is right for you.
Take medicine to control your blood pressure. Talk to your provider about which medicines are safe for your baby.
Take aspirin in the second trimester, if you are at risk of preeclampsia and your provider recommends aspirin.
Visit your provider more often to monitor your condition and your baby's growth rate and heart rate.

If you have eclampsia, HELLP syndrome, or a severe case of preeclampsia, you will most likely need to go to the hospital. Treatment often includes medicines. Your provider may also recommend delivering the baby early. They will make the decision based on:

How severe the condition is
The possible risks to you and your baby
How far along the pregnancy is

The goal is to lower the risks to you while giving your baby as much time as possible to mature before delivery.

The symptoms of preeclampsia can last after delivery, but they usually go away within 6 weeks.

[Learn More in MedlinePlus]

Preeclampsia

Preeclampsia is a complication of pregnancy in which affected women develop high blood pressure (hypertension); they can also have abnormally high levels of protein in their urine (proteinuria). This condition usually occurs in the last few months of pregnancy and often requires early delivery of the infant. However, this condition can also appear shortly after giving birth (postpartum preeclampsia).

Many women with mild preeclampsia do not feel ill, and the condition is often first detected through blood pressure and urine testing in their doctor's office. In addition to hypertension and proteinuria, signs and symptoms of preeclampsia can include excessive swelling (edema) of the face or hands and a weight gain of more than 3 to 5 pounds in a week due to fluid retention. Affected women may also experience headaches, dizziness, irritability, shortness of breath, a decrease in urination, upper abdominal pain, and nausea or vomiting. Vision changes may develop, including flashing lights or spots, increased sensitivity to light (photophobia), blurry vision, or temporary blindness.

In many cases, symptoms of preeclampsia go away within a few days after the baby is born. In severe cases, however, preeclampsia can damage the mother's organs, such as the heart, liver, and kidneys, and can lead to life-threatening complications. Extremely high blood pressure in the mother can cause bleeding in the brain (hemorrhagic stroke). The effects of high blood pressure on the brain (hypertensive encephalopathy) may also result in seizures. If seizures occur, the condition is considered to have worsened to eclampsia, which can result in coma. About 1 in 200 women with untreated preeclampsia develop eclampsia. Eclampsia can also develop without any obvious signs of preeclampsia.

Between 10 and 20 percent of women with severe preeclampsia develop another potentially life-threatening complication called HELLP syndrome. HELLP stands for hemolysis (premature red blood cell breakdown), elevated liver enzyme levels, and low platelets (cells involved in blood clotting), which are the key features of this condition.

Severe preeclampsia can also affect the fetus, with impairment of blood and oxygen flow leading to growth problems or stillbirth. Infants delivered early due to preeclampsia may have complications associated with prematurity, such as breathing problems caused by underdeveloped lungs.

Women who have had preeclampsia have approximately twice the lifetime risk of heart disease and stroke than do women in the general population. Researchers suggest that preeclampsia, heart disease, and stroke may share common risk factors. Women who have diseases such as obesity, hypertension, heart disease, diabetes, or kidney disease before they become pregnant have an increased risk of developing preeclampsia. Preeclampsia is most likely to occur in a woman's first pregnancy, although it can occur in subsequent pregnancies, particularly in women with other health conditions.