ICD10BillableValid for clinical use
ICD-10 Code O99.012: Anemia complicating pregnancy, second 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 anemia complicating pregnancy, childbirth, or the puerperium. The most accurate code depends on the maternal timing context and whether the chart later identifies a more specific anemia type or cause.
When is it used?
- May be used when a clinician documents anemia complicating pregnancy, second 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, prenatal, inpatient, and postpartum documentation where maternal anemia affects pregnancy monitoring, delivery planning, or recovery follow-up.
- Coding and utilization-review workflows where trimester or delivery timing is known and anemia materially affects maternal care.
Common workup
- Common related testing on this page includes Complete blood count, Ferritin, Iron studies.
- Related procedures or service context already linked on this page include Obstetric ultrasound, Fetal nonstress testing.
Common management context
- Maternal-anemia follow-up often includes hemoglobin or CBC review, iron-status evaluation context, medication or supplement review, and monitoring for delivery-related blood-loss risk.
- Documentation usually becomes more specific when the chart identifies iron deficiency, blood loss, chronic disease, or the exact pregnancy, childbirth, or puerperium timing.
- Specialist context already linked on this page includes Obstetrician, Gynecologist, Hematologist.
🔍Key distinctions
Important notes
- This ICD-10 family is used when maternal anemia complicates pregnancy-related care, but separate codes may still be needed when the anemia type or underlying cause is clearly documented.
- Trimester and delivery timing matter, while more specific anemia-type documentation can add clinical context beyond this maternal-complication code alone.
- This title reflects anemia complicating pregnancy, which is coded separately from anemia during childbirth or the puerperium.
- Trimester detail is part of the maternal-anemia code choice, so documentation that clearly states first, second, or third trimester affects specificity.
Related codes to consider
O99.011Anemia complicating pregnancy, first trimester
Related maternal-anemia ICD-10 code; documentation often becomes more specific when the chart identifies trimester, delivery timing, or the underlying anemia cause.
O99.013Anemia complicating pregnancy, third trimester
Related maternal-anemia ICD-10 code; documentation often becomes more specific when the chart identifies trimester, delivery timing, or the underlying anemia cause.
O99.019Anemia complicating pregnancy, unspecified trimester
Related maternal-anemia ICD-10 code; documentation often becomes more specific when the chart identifies trimester, delivery timing, or the underlying anemia cause.
Code hierarchy
chapter
15Pregnancy, childbirth and the puerperium (O00-O9A)
block
O94-O9AOther obstetric conditions, not elsewhere classified
category
O99Other maternal diseases classifiable elsewhere but complicating pregnancy, childbirth and the puerperium
category
O99.0Anemia complicating pregnancy, childbirth and the puerperium
category
O99.01Anemia complicating pregnancy
currentO99.01
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
ObstetricianGynecologistHematologist
Related tests
Complete blood count
Commonly reviewed when assessing anemia complicating pregnancy.
Ferritin
May help evaluate iron deficiency in pregnancy-related anemia workup.
Iron studies
May be reviewed when anemia in pregnancy raises concern for iron deficiency.
Related procedures
Obstetric ultrasound
May appear in pregnancy follow-up pathways when maternal diseases complicate pregnancy and fetal well-being is monitored.
Fetal nonstress testing
May be used in selected higher-risk pregnancy monitoring pathways.
Related codes
Sibling codes
Coding guidelines
Common synonyms
Anemia complicating pregnancy, second trimester
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.