Genetic Testing for Infertility: Which Tests the Data Supports, and Which It Does Not

Genetic testing explains a minority of infertility cases directly and a much larger share of future-pregnancy risk indirectly. A chromosome test finds an answer in roughly 3% to 6% of infertile patients, while carrier screening finds at least one recessive variant in more than half of healthy people.

Every rate below comes from a peer-reviewed study linked to its PubMed record, or from a guideline published by ESHRE, ASRM or ACMG, compiled by the ProIVF editorial team and reviewed by our medical advisory board.

What does a genetic workup for infertility actually include?

Four tiers, in the order clinics usually reach them.

• Tier 1, chromosome number and structure (karyotype): a blood test that counts and photographs your 46 chromosomes, answering whether a balanced translocation or an extra X chromosome is the cause.
• Tier 2, Y-chromosome microdeletion (AZF): a PCR test on the man’s blood that looks for missing segments on the long arm of the Y, where sperm production genes sit.
• Tier 3, single-gene and X-linked tests: FMR1 repeat sizing for diminished ovarian reserve (a lower egg supply than expected for age), and gene-specific tests when a family history points at one condition.
• Tier 4, expanded carrier screening: one next-generation sequencing panel covering tens to hundreds of recessive and X-linked conditions in both partners.

The AUA/ASRM guideline framework sets the practice threshold: karyotype for men with non-obstructive azoospermia and for men with severe oligozoospermia below 5 million sperm per mL. A 2025 review in Fertility and Sterility argues that threshold is too high, since cytogenetic anomalies are also increased below 20 million per mL compared with never-tested fertile men (PMID 40311997).

How often is a chromosome test abnormal in infertility?

Between 3% and 6%, depending on the population tested, and male infertility is where it shows up most.

• In a narrative review of chromosome defects in male factor infertility, karyotype anomalies were present in approximately 6% of men with infertility (PMID 40311997).
• Among 3,500 Iranian infertile patients, abnormalities were detected in 114 (3.257%), split 70 men (61.4%) and 44 women (38.6%) (PMID 37543931).
• In a Romanian series, 94.99% of infertile patients had a normal karyotype and 5.01% did not; numerical abnormalities appeared in 1.14% of men and 0.62% of women, structural ones in 1.38% of men and 1.87% of women (PMID 26929902).
• In men with non-obstructive infertility, about 25% carry a chromosomal abnormality or a Y-chromosome microdeletion, and among the abnormal karyotypes the most common was 47,XXY (Klinefelter syndrome) in 27% of cases (PMID 35197703).

Those are different numbers for different questions: 3% to 6% is the rate across an infertility clinic, while 25% is the rate in the small subgroup whose semen analysis shows no sperm at all.

Does an abnormal parental karyotype change the chance of a baby?

It changes the early pregnancy numbers more than the end point.

A systematic review and meta-analysis of couples with recurrent pregnancy loss compared abnormal-karyotype carriers with non-carriers. Carriers had a lower first-pregnancy live birth rate, 58.5% versus 71.9% (odds ratio 0.55, 95% CI 0.46 to 0.65), and a higher miscarriage rate, 53.0% versus 34.7% (PMID 36175209). The gap narrowed over time: accumulated live birth was 81.4% versus 74.8%, not statistically significant.

Translocations drove the risk; inversions did not. First-pregnancy live birth was 52.9% versus 72.4% for translocation carriers (95% CI 0.31 to 0.61), with no significant difference for inversion.

A single-center cohort of 3,235 couples with two or more losses before 20 weeks found chromosome aberrations in 121 couples (3.74%): 46 balanced translocations, 13 Robertsonian translocations (two chromosomes fused into one), 42 inversions and 20 numerical changes. Over two years, carriers had a healthy newborn at essentially the same rate as non-carriers, 72.7% versus 71.2% (adjusted P = 0.968), and the authors concluded natural conception “may be also a good alternative rather than PGD” (PMID 34645840).

When is Y-chromosome microdeletion testing ordered?

It is ordered for men whose semen analysis shows no sperm or almost none, because the finding is concentrated there.

• In 292 north Indian infertile men with non-obstructive azoospermia or oligozoospermia, Y microdeletion frequency was 8.5% overall — 9.2% in azoospermic men and 7.1% in low-count men, with AZFc the most commonly deleted region (PMID 34238779).
• In a retrospective study of 32,055 Chinese men, Y-chromosome polymorphic variants occurred in 1.19%, and AZF deletions were detected in 28.92% of men with the shortened Yqh variant (46,XYqh-) versus 2.50% in another subgroup; AZFb+c was the most common deletion at 78.57% (PMID 38270748).
• Laboratory genetic testing is advised for men with non-obstructive infertility because “any abnormal finding can yield substantial consequences to assisted reproductive techniques or fertility treatment” (PMID 35197703).

A deletion is not a dead end for parenthood, but a decision point: it changes which retrieval procedure is offered, whether donor sperm is discussed, and what a male child would inherit. Genetic counseling is part of the result, not an add-on.

Should both partners have carrier screening before IVF?

The professional guidance moved from “test by ancestry” to “offer to everyone.”

“Reproductive decision making is the established metric for clinical utility of population-based carrier screening.” — ACMG practice resource, Genetics in Medicine, 2021 (PMID 34285390)

That resource recommends offering carrier screening to all individuals during pregnancy or preconception, moving away from panels tied to one racial or ethnic group; cystic fibrosis was the first panethnic condition, then spinal muscular atrophy.

The yields are large, because most carriers are healthy.

• 10,476 preconception and prenatal couples in China tested for 11 recessive conditions: 27.49% of individuals without a family history carried at least one, and 255 couples (2.43%) were at elevated risk of an affected baby, 65 of them missed by the thalassemia-only program then in place (PMID 30275481).
• A 220-disease NGS panel in 3,024 people in southern China found a 62.3% carrier rate, with 23.2% carrying variants for multiple diseases; 128 couples shared a gene, giving a theoretical affected-offspring rate of 2.12% (PMID 39380106).
• In Barcelona, 1,301 individuals tested through a reproductive medicine program were 56% carriers of at least one condition, and 3% of previously assigned donations were high-risk before matching was corrected (PMID 26990548).
• SMA carrier frequency in a Korean population was 1.83%, or 1 in 55 (95% CI 1 in 79 to 1 in 38), measured by SMN1 copy number (PMID 32067433).
• Fragile X premutation carriers in a general obstetric population ran 0.43%, 95% of them in the 55 to 90 CGG repeat range (PMID 35129870); older population estimates put the premutation at 1 in 246 to 1 in 468 women (PMID 11545690).

Does a carrier panel detect the same amount in every ancestry?

No, and this is the single most under-explained limitation in the field, especially for East Asian patients using United States or European panels.

In an Australian study of CFTR (cystic fibrosis gene) screening built on national registry data, panels of 25 to 50 variants initially captured about 92% to 95% of CFTR variants. That capture fell to 87% to 92% over ten years as the population changed. Detection by self-reported ancestry was 84% to 90% in White (European) groups but 25% to 69% in Asian groups, with Black at 62% to 91%, Middle Eastern 51% to 55% and Pacific Islander 17% to 33% (PMID 42225447).

Read that as a residual-risk problem: a negative CF result carries different probability for Chinese, South Asian or Pacific Islander patients than for northern European ones, and the panel version matters more than the laboratory brand.

What does genetic testing cost, and is screening worth it?

Health-economics evaluations put a number on it, and the preconception window is where the value sits.

• An Ontario health technology assessment priced universal carrier screening for cystic fibrosis, fragile X, hemoglobinopathies and thalassemia, and SMA: preconception screening cost C$29,106 per additional at-risk pregnancy detected and C$367,731 per affected birth averted, against about C$29,759 and C$431,807 in the prenatal window, and five-year universal prenatal funding was estimated at C$128 million to C$305 million versus C$1.3 million to C$2.7 million for risk-based preconception screening (PMID 37637488).
• A 176-condition expanded carrier screen modeled 100,000 pregnancies: 290 affected pregnancies, each adding on average 26 undiscounted life-years of mortality and about US$1,100,000 in lifetime cost; preconception screening was cost-effective under a US$50,000-per-life-year threshold (PMID 30760891).
• Australia’s national evaluation found expanded reproductive carrier screening cost-saving against no screening and cost-effective against three-condition screening at A$6,287 per quality-adjusted life year gained (PMID 36789890).

The price is defensible because of timing: a result before stimulation lets a clinic change the plan — IVF with PGT-M (preimplantation genetic testing for one known gene variant), donor gametes, or natural conception with monitoring. The same result after transfer only informs the next cycle.

Which infertility genetic tests should you skip?

Two, and the evidence against them is explicit.

• MTHFR polymorphism testing: ACMG’s practice guideline states that MTHFR testing “has minimal clinical utility and, therefore should not be ordered as a part of a routine evaluation for thrombophilia,” after meta-analyses disproved the assumed links to venous thromboembolism and coronary disease (PMID 23288205), yet ACMG still describes it as frequently ordered, usually inside a clotting workup.
• Routine inherited thrombophilia panels for repeated loss: a systematic review and meta-analysis did find associations — factor V Leiden odds ratio 2.44 (95% CI 1.96 to 3.03), prothrombin gene mutation 2.08 (1.61 to 2.68) and protein S deficiency 3.45 (1.15 to 10.35), with no association for antithrombin or protein C deficiency — but only 39 of the included studies controlled for confounders, and heterogeneity was high (PMID 33575779). Treat a positive result as a discussion with a hematologist, not as an automatic heparin decision.

POI is also more common than previously stated. The ESHRE-endorsed guideline on premature ovarian insufficiency, published in Fertility and Sterility 2025, reports a 3.5% prevalence and simplifies diagnosis to one elevated FSH (follicle-stimulating hormone) reading above 25 IU/L plus symptoms (PMID 39652037). Genetic causes belong in that conversation: its test list includes FMR1 and karyotype, not immune or clotting panels.

What two couples did with their results

Both accounts below are composites constructed from patterns documented in the literature and in clinic practice. Names, identity details and amounts are illustrative estimates, not identifiable medical records and not price quotes.

Lian, 33, Chengdu → Los Angeles: the panel that changed the plan

Lian and her husband both tested negative for the conditions on her state-mandated cystic fibrosis panel, then ordered a 300-plus-condition expanded carrier screen through a US laboratory at about $750 for the couple. His result carried a CFTR variant she did not.

Their counselor explained the ancestry caveat in the same appointment: a 25-to-50-variant panel recovers only about a quarter to two-thirds of CFTR variants in Asian patients, so “negative” on a short panel is not zero risk. They proceeded to IVF with PGT-M for the paired variant.

“We were told we were compatible for one gene we had never heard of,” Lian said. “Nobody had explained that the panel length is the whole question.”

Tom, 36, and Rachel, 35, Ohio: a balanced translocation and no IVF

Rachel had three losses before 14 weeks. Their karyotype showed a balanced reciprocal translocation in Rachel, and the clinic offered two paths: IVF with PGT-SR (embryo testing for the rearrangement) or timed natural conception with early monitoring.

They chose natural conception because published cohorts put accumulated live birth for carriers close to the non-carrier rate, and because their balance-sheet question was time, not money. Their next attempt was viable at 12 weeks’ gestation, and they delivered a live baby at term.

“The scary number was the 58.5 versus 71.9 percent,” Rachel said. “The number that decided it for us was 81.4 versus 74.8 — by the end, the same.”

Questions to ask before you pay for a test

A test earns its price only when a positive result changes your treatment plan, so ask these five before you consent.

1. Which specific gene or chromosome does this test look at, and what is the detection rate for my ancestry?
2. What exactly will change in my treatment plan if the result is positive, and what changes if it is negative?
3. Is this a karyotype, a microdeletion PCR, or a sequencing panel, and how long does each take to return?
4. Will a genetic counselor review the result with me in writing, and is that included in the price?
5. If we are carriers for the same gene, is PGT-M available here, and how many cycles of it are realistic?

FAQ

Q: Is genetic testing required before IVF?

No single test is universally required before IVF. Karyotype and AZF testing are standard for men with non-obstructive azoospermia or a count below 5 million sperm per mL (PMID 40311997), and ACMG recommends carrier screening for everyone planning a pregnancy or already pregnant (PMID 34285390).

Q: How common are chromosome problems in infertile men?

About 6% of men with infertility have a karyotype anomaly, and 47,XXY (Klinefelter syndrome) accounts for 27% of abnormal results. Counting deletions, roughly a quarter of men with no sperm in the ejaculate carry one (PMID 40311997, PMID 35197703).

Q: Does carrier screening find anything in people with no family history?

Yes. 27.49% of tested individuals with no self-reported family history carried at least one of 11 recessive conditions, and 2.43% of couples faced an elevated risk for an affected child — 65 of those 255 would have been missed by a thalassemia-only program (PMID 30275481).

Q: Why do cystic fibrosis results differ by ethnicity?

Because a panel only detects the variants it contains. Detection of CFTR variants was 84% to 90% in White European groups but 25% to 69% in Asian groups, and larger or ancestry-matched panels narrow the gap (PMID 42225447).

Q: Is MTHFR testing useful for recurrent miscarriage?

ACMG says no: its 2013 practice guideline states the test has minimal clinical utility and should not be ordered as part of routine thrombophilia evaluation (PMID 23288205). The related clotting-panel evidence is weak too, since only 39 of the studies in the recurrent-loss meta-analysis controlled for confounders.

Q: Will a balanced translocation stop us from having a healthy child?

Not usually. First-pregnancy live birth was lower (58.5% versus 71.9%), but accumulated live birth was 81.4% versus 74.8%, a non-significant difference, and in one cohort healthy newborn rates were 72.7% versus 71.2% (PMID 36175209, PMID 34645840).

Q: How much does expanded carrier screening cost?

Commercially, couple panels are typically priced in the hundreds of US dollars rather than thousands. The economics literature is about the system cost per detected risk: C$29,106 per additional at-risk pregnancy in the preconception window (PMID 37637488).

Q: Does testing change the IVF protocol itself?

It can, in three specific ways: PGT-M for a known paired variant, PGT-SR for a structural rearrangement, and donor gametes when a couple is incompatible for an X-linked gene. One program excluded 1.7% of oocyte donors on that X-linked basis (PMID 26990548).

Where to go from here

Order tests in the sequence the evidence supports: semen analysis and ovulation assessment first, then karyotype and AZF if the male result is severe or losses have repeated, then carrier screening for both partners before stimulation, and thrombophilia or immune panels only when a hematologist asks for them.

Ask one question of every test offered: what changes if this comes back positive. If the honest answer is “nothing,” decline it and put the money into the cycle. Our PGT genetic screening guide explains how embryo-side testing differs from parent-side testing; related reads are azoospermia, semen analysis, recurrent pregnancy loss and low AMH. The ASRM patient fact sheet on genetic testing and the ESHRE premature ovarian insufficiency guideline are the two non-commercial starting points. Compare clinics in the hospital directory, or send laboratory reports through the contact page.

This article is health information, not individual medical advice or genetic counseling. Only a qualified genetic counselor or your treating clinician can interpret a specific result for your family. Where it conflicts with the written instructions from your own clinic, follow your clinic.

Every rate, odds ratio and cost figure above links to its PubMed record; guideline statements are cited to ESHRE and ACMG publications. The two patient accounts are composites, and the figures inside them are illustrative and not individually sourced. The ProIVF Medical Advisory Board reviewed the final text. About the team: About us.

Last updated: October 9, 2026