ICD10BillableValid for clinical use
ICD-10 Code O10.419: Pre-existing secondary hypertension complicating pregnancy, unspecified trimester
Reviewed by HealthAssure Clinical TeamUpdated 21 May 2026
What is this code?
ICD-10 codes are diagnosis classification codes used in healthcare records, reporting, coding workflows, and billing support. This code sits within the broader ICD-10 area for Pregnancy, childbirth and the puerperium (O00-O9A).
đź“‹Clinical overview
This ICD-10 code is commonly used when documentation describes chronic or pre-existing hypertension complicating pregnancy, childbirth, or the puerperium. The most accurate code depends on whether the hypertension is uncomplicated or linked to heart or kidney disease, plus the trimester or delivery timing.
When is it used?
- May be used when a clinician documents pre-existing secondary hypertension complicating pregnancy, unspecified trimester in a patient's medical record.
- May appear in hospital records, claims, referrals, and clinical documentation.
- This code can be used as a clinically usable diagnosis entry in standardized coding workflows.
What it does not mean
- A code alone does not explain severity, treatment plan, or outcome.
- A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
đź©şClinical context
When commonly used
- Obstetric, maternal-fetal medicine, inpatient, and prenatal documentation where chronic hypertension affects pregnancy monitoring, delivery planning, or postpartum follow-up.
- Coding, utilization-review, and maternal-risk workflows where trimester, delivery timing, and organ involvement change the final diagnosis detail.
Common workup
- Common related testing on this page includes Urine protein assessment, Serum creatinine, Platelet count, Liver function tests.
- Related procedures or service context already linked on this page include Obstetric ultrasound, Fetal nonstress testing, Biophysical profile.
Common management context
- Maternal-hypertension follow-up often includes blood-pressure monitoring, medication review, urine and kidney assessment context, fetal surveillance, and preeclampsia-risk monitoring.
- Documentation usually becomes more specific when the chart identifies pre-existing hypertension, trimester, childbirth or puerperium timing, and whether heart or kidney disease is also documented.
- Specialist context already linked on this page includes Obstetrician, Gynecologist, Cardiologist, Maternal-Fetal Medicine Specialist.
🔍Key distinctions
Important notes
- Maternal-hypertension ICD-10 coding is context-sensitive and usually depends on whether the hypertension predates pregnancy and whether the encounter is during pregnancy, childbirth, or the puerperium.
- Trimester detail and associated heart or kidney disease often matter for maternal-hypertension coding, while gestational hypertension and preeclampsia are coded separately from pre-existing hypertension complicating pregnancy.
Related codes to consider
O10.411Pre-existing secondary hypertension complicating pregnancy, first trimester
Related maternal-hypertension ICD-10 code; documentation often becomes more specific when the chart identifies chronic versus pregnancy-specific hypertension, trimester, delivery timing, or heart/kidney involvement.
O10.412Pre-existing secondary hypertension complicating pregnancy, second trimester
Related maternal-hypertension ICD-10 code; documentation often becomes more specific when the chart identifies chronic versus pregnancy-specific hypertension, trimester, delivery timing, or heart/kidney involvement.
O10.413Pre-existing secondary hypertension complicating pregnancy, third trimester
Related maternal-hypertension ICD-10 code; documentation often becomes more specific when the chart identifies chronic versus pregnancy-specific hypertension, trimester, delivery timing, or heart/kidney involvement.
Code hierarchy
chapter
15Pregnancy, childbirth and the puerperium (O00-O9A)
block
O10-O16Edema, proteinuria and hypertensive disorders in pregnancy, childbirth and the puerperium
category
O10Pre-existing hypertension complicating pregnancy, childbirth and the puerperium
category
O10.4Pre-existing secondary hypertension complicating pregnancy, childbirth and the puerperium
category
O10.41Pre-existing secondary hypertension complicating pregnancy
currentO10.41
Where you may see this code
You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records.
Related specialists
ObstetricianGynecologistCardiologistMaternal-Fetal Medicine Specialist
Related tests
Urine protein assessment
May be reviewed when evaluating hypertensive disorders in pregnancy.
Serum creatinine
Often reviewed when assessing kidney involvement in hypertensive disorders of pregnancy.
Platelet count
May be relevant when monitoring pregnancy-related hypertension complications.
Liver function tests
May be reviewed when hypertensive disorders in pregnancy raise concern for maternal complications.
Related procedures
Obstetric ultrasound
Commonly part of fetal growth and pregnancy follow-up pathways in hypertensive disorders of pregnancy.
Fetal nonstress testing
May be used in selected higher-risk pregnancy monitoring pathways.
Biophysical profile
May appear in fetal surveillance pathways for higher-risk pregnancies.
Related codes
Sibling codes
Coding guidelines
Common synonyms
Pre-existing secondary hypertension complicating pregnancy, unspecified trimesterPre-existing secondary hypertension complicating pregnancy
Frequently asked questions
About this content
This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.