For IVF pregnancies, the core ICD-10 codes are: N97.x for female infertility and N46.x for male infertility as the diagnosis, Z31.2 for the IVF treatment encounter itself, N98.x for complications such as OHSS (ovarian hyperstimulation syndrome), and Z34 or Z35.0 for prenatal care once pregnancy is confirmed. The sections below decode each stage of the IVF journey and show how these codes work on real bills and medical records.
Data in this article comes from the WHO ICD-10 classification (2019 edition), the ICD-10-CM code reference published by AAPC Codify, and peer-reviewed medical literature. It was compiled by the ProIVF Medical Editorial Team and reviewed by the ProIVF Medical Advisory Board.
Which ICD-10 Codes Appear on an IVF Record?
An IVF pregnancy touches four chapters of ICD-10. These are the codes you are most likely to see on a bill or medical record:
| Stage of IVF journey | ICD-10 code | Meaning |
|---|---|---|
| Infertility diagnosis (female) | N97.0–N97.9 | Female infertility by cause (ovulatory, tubal, uterine, etc.) |
| Infertility diagnosis (male) | N46.0–N46.9 | Male infertility (azoospermia, oligospermia, etc.) |
| IVF treatment encounter | Z31.2 | In vitro fertilization — admission for harvesting or implantation of ova |
| Artificial insemination | Z31.1 | IUI (intrauterine insemination) encounter |
| Other assisted methods | Z31.3 | ICSI and other assisted fertilization techniques |
| Complication: OHSS | N98.1 | Hyperstimulation of ovaries |
| Complication: embryo transfer | N98.2, N98.3 | Complications of attempted introduction of fertilized ovum / embryo |
| Pregnancy confirmed | Z32.1 | Pregnancy confirmed |
| Prenatal care, normal | Z34.0 / Z34.8 / Z34.9 | Supervision of normal pregnancy |
| Prenatal care with infertility history | Z35.0 | Supervision of pregnancy with history of infertility |
| Genetic counseling | Z31.5 | Procreative genetic counseling |
The most common code sequence is N97.x (or N46.x) plus Z31.2 during treatment, switching to Z35.0 once pregnancy is confirmed. Z35.0 signals to the care team and the insurer that this pregnancy followed infertility treatment, which can trigger closer monitoring.
How Are Infertility Diagnoses Coded, N97.x and N46.x?
Before IVF can begin, the medical record must document why the patient is infertile. ICD-10 groups female infertility under N97 (Female infertility) and male infertility under N46 (Male infertility).
N97 — Female Infertility
Both the WHO ICD-10 and the US ICD-10-CM define N97 as female infertility, with the note “Includes: inability to achieve a pregnancy” (see the AAPC Codify ICD-10-CM reference). Subcodes specify the cause:
| Code | Official descriptor |
|---|---|
| N97.0 | Female infertility associated with anovulation |
| N97.1 | Female infertility of tubal origin |
| N97.2 | Female infertility of uterine origin |
| N97.8 | Female infertility of other origin |
| N97.9 | Female infertility, unspecified |
ICD-10-CM excludes from N97 infertility linked to pituitary/hypothalamic disease (E23.0), polycystic ovarian syndrome (E28.2), and cervical/vaginal factors (N88.3) — those conditions are coded to their own chapters.
N46 — Male Infertility
| Code | Official descriptor |
|---|---|
| N46.0 | Azoospermia |
| N46.1 | Oligospermia |
| N46.8 | Other male infertility |
| N46.9 | Male infertility, unspecified |
When male factor is the reason for IVF, the man’s record carries an N46 code while the female partner’s record carries the infertility evaluation codes (commonly N97.9, or Z31.4 during the workup). In the US, both sides matter for insurance preauthorization.
What If the Cause Is Unknown?
When no specific cause is found, clinicians use N97.9 (female infertility, unspecified) for the diagnosis and Z31.4 (encounter for procreative investigation and testing) for the workup phase. Unexplained infertility is one of the most common diagnoses leading to IVF.
What Does Z31.2 Mean in IVF Coding?
Once a couple proceeds with IVF, treatment encounters fall under Z31 (Encounter for procreative management). These are “Z codes” — factors influencing health status and contact with health services — not disease codes.
The WHO definition of Z31.2 is “Admission for harvesting or implantation of ova” — in plain language, the IVF cycle itself: egg retrieval, lab fertilization, and embryo transfer. On a bill it usually appears alongside the separate procedure codes for retrieval and transfer.
Other Z31 Subcodes
| Code | Official descriptor | Used for |
|---|---|---|
| Z31.0 | Tuboplasty or vasoplasty after previous sterilization | Reversal of tubal ligation / vasectomy |
| Z31.1 | Artificial insemination | IUI (intrauterine insemination) |
| Z31.2 | In vitro fertilization | IVF: egg retrieval, fertilization, embryo transfer |
| Z31.3 | Other assisted fertilization methods | ICSI (intracytoplasmic sperm injection) and related techniques |
| Z31.4 | Procreative investigation and testing | Semen analysis, fertility workup |
| Z31.5 | Genetic counselling | Pre-IVF genetic counseling |
| Z31.6 | General counselling and advice on procreation | Fertility counseling |
| Z31.7 | Procreative management for gestational carrier | Surrogacy / gestational carrier arrangements |
| Z31.8 | Other procreative management | Other fertility treatment encounters |
| Z31.9 | Procreative management, unspecified | Unspecified encounter |
ICD-10 explicitly excludes “complications associated with artificial fertilization” from the Z31 block — they are classified to N98 instead (WHO ICD-10, 2019 edition). A routine IVF cycle is Z31.2, but if OHSS develops, the complication gets its own N98.1 code.
How Is an IVF Pregnancy Coded After a Positive Test?
After the beta-hCG (human chorionic gonadotropin) blood test turns positive, coding moves into ICD-10’s pregnancy-supervision chapter.
Z32.1 — Pregnancy Confirmed
The encounter where a pregnancy test is confirmed positive is coded Z32.1 (Pregnancy confirmed). For IVF patients this is typically the blood test about two weeks after transfer.
Z34 — Supervision of Normal Pregnancy
Once prenatal care begins with an ongoing normal pregnancy, it is supervised under Z34:
| Code | Official descriptor |
|---|---|
| Z34.0 | Supervision of normal first pregnancy |
| Z34.8 | Supervision of other normal pregnancy |
| Z34.9 | Supervision of normal pregnancy, unspecified |
Z35.0 — Pregnancy With a History of Infertility
The most relevant prenatal code for IVF patients is Z35.0 (Supervision of pregnancy with history of infertility), part of the Z35 high-risk pregnancy supervision category. Many clinics and payers use Z35.0 for IVF pregnancies because the patient has a documented infertility history, which can justify extra monitoring, early ultrasounds, or specialized obstetric care.
In the US, putting Z35.0 (rather than only Z34.x) on prenatal claims tells the insurer and the care team that this pregnancy follows infertility treatment. That supports coverage for additional ultrasounds, earlier fetal monitoring, and sometimes a higher level of maternity care.
How Are IVF Complications Coded, N98.x?
ICD-10 reserves N98 (Complications associated with artificial fertilization) for problems caused by assisted reproduction. When an IVF patient develops a complication, the record carries the N98 code — instead of, or in addition to, the Z31.2 treatment code.
| Code | Official descriptor | Clinical example |
|---|---|---|
| N98.0 | Infection associated with artificial insemination | Post-IUI infection |
| N98.1 | Hyperstimulation of ovaries | OHSS — ovarian hyperstimulation syndrome |
| N98.2 | Complications of attempted introduction of fertilized ovum following in vitro fertilization | Difficulty/complication during transfer of the fertilized egg |
| N98.3 | Complications of attempted introduction of embryo in embryo transfer | Complication during embryo transfer |
| N98.8 | Other complications associated with artificial fertilization | Other treatment-related complications |
| N98.9 | Complication associated with artificial fertilization, unspecified | Unspecified complication |
OHSS (N98.1) deserves special attention as the most discussed IVF complication; the AAPC ICD-10-CM reference lists hyperstimulation of ovaries under N98.1. Mild OHSS affects roughly 20–33% of stimulated cycles and moderate OHSS about 3–8%. When a patient is hospitalized for OHSS, N98.1 is the primary diagnosis on the claim.
How Do These Codes Work in Real IVF Billing?
Understanding the codes helps you read your own medical bills — and, in the US, helps your clinic submit insurance claims that get approved.
What Is the Difference Between ICD-10 and ICD-10-CM?
WHO publishes the international ICD-10; the US uses ICD-10-CM (Clinical Modification), which is more granular — extra characters can encode laterality and encounter type. The codes in this article are valid in both systems, but always confirm the exact code with your clinic’s billing department, since local editions (ICD-10-AM in Australia, ICD-10-GM in Germany) may differ at the subcode level.
Why Do Diagnosis Codes Decide Insurance Coverage?
In the US, most policies cover IVF only when a medical diagnosis of infertility is documented, which means three things must line up:
- The infertility diagnosis (N97.x / N46.x) must be on the record.
- The treatment encounter code (Z31.2) links the service to that diagnosis.
- Once pregnant, Z35.0 supports maternity claims tied to the infertility history.
A common denial reason is “diagnosis not covered” — often because the claim carried only the Z31.2 encounter code without an N97.x diagnosis, or the reverse. If your claim is denied, check that both the diagnosis and encounter codes are present.
What Does a Billing Scenario Look Like?
| Visit | Diagnosis code | Encounter code |
|---|---|---|
| Initial fertility workup | N97.9 (unspecified infertility) | Z31.4 (procreative investigation) |
| IVF cycle — egg retrieval & transfer | N97.1 (tubal origin, for example) | Z31.2 (in vitro fertilization) |
| OHSS hospitalization | N98.1 (hyperstimulation) | — |
| First prenatal visit after IVF | Z35.0 (pregnancy with history of infertility) | Z32.1 (pregnancy confirmed) |
| Ongoing normal prenatal care | Z35.0 | — |
FAQ
Q: What is the ICD-10 code for IVF treatment?
The IVF treatment encounter is Z31.2 (In vitro fertilization), defined by WHO as “Admission for harvesting or implantation of ova.” The underlying infertility is coded separately as N97.x (female) or N46.x (male), and because Z31.2 is an encounter code rather than a procedure code, one IVF bill usually lists several codes.
Q: What ICD-10 code is used for an IVF pregnancy?
After confirmation, most IVF patients see Z35.0 (Supervision of pregnancy with history of infertility) on prenatal claims, or Z34.x for a normal pregnancy; the confirmation visit itself is Z32.1. Singleton and twin pregnancies use the same code — Z35.0 records the infertility history, not the number of babies.
Q: What is the ICD-10 code for OHSS after IVF?
OHSS is coded N98.1 (Hyperstimulation of ovaries) under complications of artificial fertilization. Mild OHSS affects roughly 20–33% of stimulated cycles and moderate OHSS 3–8%; most mild and moderate cases resolve with outpatient care, while hospitalization is mainly needed for severe OHSS.
Q: Is IVF coded differently from IUI?
Yes. IUI (intrauterine insemination) is Z31.1, IVF is Z31.2, and other assisted methods such as ICSI are Z31.3.
Using the wrong encounter code is a common reason for claim denials. If you are new to the treatment itself, our step-by-step IVF guide walks through each phase of a cycle.
Q: Does using Z35.0 change my prenatal care?
Potentially. The code itself does not change clinical decisions — your doctor decides on extra ultrasounds or closer monitoring based on your situation.
What Z35.0 does is document that the pregnancy follows infertility treatment, so additional surveillance is justified on the record, and it appears on ongoing prenatal claims throughout pregnancy, not just the first visit.
Q: Where can I verify these codes?
Use the authoritative sources: the WHO ICD-10 browser, the AAPC Codify ICD-10-CM reference, and the ICD-10-CM files published by CMS and the CDC. A clinic billing department or certified coder can confirm the exact code for a specific clinical situation.
How Should You Use Coding Knowledge on Your IVF Journey?
Knowing the codes is one thing; navigating treatment is another. If you are starting IVF, here is how to put this information to work:
- Ask your clinic for a diagnostic code summary. Before treatment, confirm your infertility diagnosis (N97.x / N46.x) is documented — it is the foundation of insurance coverage in the US.
- Keep a record of encounter codes. Note whether your cycle is billed as Z31.2 (IVF) or Z31.1 (IUI) so you can spot coding errors on bills.
- Understand your prenatal codes. If you get pregnant, expect Z35.0 on prenatal claims — it reflects your infertility history and supports closer monitoring.
- Compare clinics transparently. Success rates, costs, and billing practices vary widely. Use our hospital directory to compare clinics, the IVF cost guide for realistic budgets, and the IVF risks guide to understand complications like OHSS.
Questions about a specific code on your bill belong with the clinic’s billing department or a certified coder. If you are comparing clinics, our contact team can help you find centers that are transparent about pricing and coding.
Medical disclaimer: This article is for information only and does not constitute medical or billing advice. ICD-10 coding rules differ by country, payer, and clinical situation — always confirm the codes that apply to your case with your clinic’s billing department or a certified medical coder.
This article was written by the ProIVF Medical Editorial Team and reviewed by the ProIVF Medical Advisory Board, based on publicly available data from the WHO ICD-10 classification and the ICD-10-CM reference published by AAPC Codify.
Last updated: August 20, 2026
