2026 ICD-10-CM Diagnosis Code T38.4X5AAdverse effect of oral contraceptives, initial encounter
T38.4X5A is a billable ICD-10-CM diagnosis code for adverse effect of oral contraceptives, initial encounter. The 7th character A marks it as an initial encounter code, used while the patient is receiving active treatment. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 917 through 918. The code is not accepted as a principal diagnosis by the Medicare Code Editor. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Adverse effects of drugs and medicaments, initial encounter.
Code Identity
Code Classification
Code EditsBilling
Medicare Code Editor checks that affect claim validity for T38.4X5A.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Adverse reaction to oral contraceptive
- Chorea caused by oral contraceptive
- Disorder due to contraceptive use
- Drug-induced chorea
- Ethynodiol diacetate adverse reaction
- Gingival disease caused by oral contraceptive use
- Gingival enlargement exacerbated by oral contraceptive
- Headache caused by drug
- Headache caused by oral contraceptive pill
- Hypertension induced by oral contraceptive pill
- Hypertension secondary to drug
- Levonorgestrel adverse reaction
- Migraine caused by estrogen contraceptive
- Norethisterone adverse reaction
- Oral contraceptive intolerance
- Postpill amenorrhea
- Toxic chorea
Coding GuidelinesGuidance
When coding an adverse effect of a drug that has been correctly prescribed and properly administered, assign the appropriate code for the nature of the adverse effect followed by the appropriate code for the adverse effect of the drug.
The appropriate 7th character is to be added to each code from block Poisoning by, adverse effect of and underdosing of hormones and their synthetic substitutes and antagonists, not elsewhere classified (T38). Use the following options for the applicable episode of care:
- A - initial encounter
- D - subsequent encounter
- S - sequela
Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Secondary Amenorrhea
the cessation of menstruation for six months or more in a female that is not pregnant, breastfeeding or menopausal.
Table of Drugs and ChemicalsClinical
Substances in the Table of Drugs and Chemicals that reference this code family. Always confirm in the Tabular List before coding.
Patient EducationClinical
Birth Control
Birth control, also known as contraception, is the use of medicines, devices, or surgery to prevent pregnancy. There are many different types. Some are reversible, while others are permanent. Some types can also help prevent sexually transmitted infections (STIs).
The full article covers:
- What is birth control?
- What are the different types of birth control?
- What are some other forms of pregnancy prevention?
- What is emergency contraception?
- What else should I know about birth control?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert T38.4X5A to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About T38.4X5AOverview
Is T38.4X5A (Adverse effect of oral contraceptives) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report adverse effect of oral contraceptives, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character A in T38.4X5A mean?
The final character A marks the initial encounter: use it while the patient is receiving active treatment for adverse effect of oral contraceptives, such as an emergency visit or first evaluation.
What MS-DRG does T38.4X5A group to?
On inpatient claims, adverse effect of oral contraceptives, initial encounter maps to MS-DRG 917, 918, with relative weights from 0.8571 to 1.5684 depending on complications. Higher weights mean higher Medicare reimbursement.
Can T38.4X5A be a principal diagnosis?
No. The Medicare Code Editor rejects this code as a principal diagnosis because adverse effect of oral contraceptives, initial encounter describes a circumstance that influences health status rather than a current illness. Report it as a secondary diagnosis.
What is the ICD-9 equivalent of T38.4X5A?
Under the General Equivalence Mappings, adverse effect of oral contraceptives, initial encounter converts to ICD-9-CM 995.29 (adv eff med/biol NEC/NOS) and E932.2 (adv eff ovarian hormones). The mapping is approximate, so confirm the match fits the documentation.
Footnotes
[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.
