Choosing between PGD FISH 9 and PGT-A 24-chromosome testing is one of the most consequential decisions in a surrogacy journey. Both screen embryos for chromosomal abnormalities before transfer — but they do so with very different technologies, levels of detail, and price points.
If you're considering surrogacy in Ukraine, Georgia, or Armenia, your clinic will likely offer both options. Understanding what each test actually does — and what it can't do — will help you have a more informed conversation with your reproductive specialist.
What is preimplantation genetic testing?
Preimplantation genetic testing (PGT) is a laboratory procedure performed on embryos created through IVF, before they are transferred into a surrogate's uterus. The goal is straightforward: identify embryos with the correct number of chromosomes and exclude those with abnormalities that would result in failed implantation, miscarriage, or a child born with a genetic condition.
The procedure itself is the same regardless of which test is used. On day 5 or 6 after fertilization, the embryologist performs a trophectoderm biopsy — removing 5-10 cells from the outer layer of the embryo (which will later become the placenta), without touching the inner cells that develop into the baby. These cells are then sent for genetic analysis.
PGD FISH 9 — the established method
PGD FISH 9 (Preimplantation Genetic Diagnosis using Fluorescence In Situ Hybridization) has been the workhorse of preimplantation genetic testing since the late 1990s. The technique uses fluorescent DNA probes that bind to specific chromosomes, making them visible under a microscope and countable.
The "9" refers to the number of chromosome pairs analysed: 13, 15, 16, 17, 18, 21, 22, X, and Y. These nine were chosen because they represent the chromosomes most commonly involved in viable abnormalities — meaning the ones that can result in a born child with a genetic condition, rather than causing very early miscarriage.
Syndromes detected by PGD FISH 9
- Down syndrome (trisomy 21) — the most common chromosomal disorder at birth
- Edwards syndrome (trisomy 18)
- Patau syndrome (trisomy 13)
- Klinefelter syndrome (47,XXY)
- Turner syndrome (45,X)
- Triple X syndrome (47,XXX)
- Jacobs syndrome (47,XYY)
- Trisomies of chromosomes 15, 16, 17, and 22
PGD FISH 9 also identifies the embryo's sex chromosomes (XX or XY), enabling sex selection — also known as gender selection or family balancing — where legally permitted.
PGT-A 24-chromosome — the comprehensive option
PGT-A 24-chromosome (Preimplantation Genetic Testing for Aneuploidy, performed via Next Generation Sequencing) is the modern standard. Instead of looking at nine chromosome pairs through a microscope, NGS reads the actual DNA sequence of all 24 chromosomes — that is, all 22 autosomes plus the X and Y sex chromosomes.
This is performed in a sophisticated embryology laboratory using high-throughput DNA sequencers. The process takes longer than FISH (typically 1-2 weeks for results) but produces far more comprehensive data.
You may also see PGT-A referred to by older or alternative names: PGS (preimplantation genetic screening), PGT-A by NGS, or simply 24-chromosome aneuploidy testing. They all describe the same modern technique.
What PGT-A 24-chromosome detects beyond FISH 9
- All aneuploidies — trisomies and monosomies of every chromosome, not just nine
- Microdeletions and microduplications — small segments of missing or extra DNA invisible to FISH
- Mosaicism — embryos with mixed normal and abnormal cells
- Sex chromosome abnormalities — same as FISH
- Sex identification for sex selection where legally permitted
Side-by-side comparison
| Feature | PGD FISH 9 | PGT-A 24-chromosome |
|---|---|---|
| Chromosomes screened | 9 pairs (13, 15, 16, 17, 18, 21, 22, X, Y) | All 24 chromosomes |
| Technology | Fluorescent probes + microscopy | Next Generation Sequencing (NGS) |
| Detection accuracy | ~90-95% for tested chromosomes | ~98-99% across all chromosomes |
| Detects microdeletions | No | Yes |
| Detects mosaicism | Limited | Yes |
| Time for results | 1-3 days | 7-14 days |
| Sex selection | Yes | Yes |
| Relative cost | Lower | Higher |
Which test should you choose?
The honest answer is: it depends on your situation. Here are the most common decision factors.
PGD FISH 9 may be appropriate if:
- You are under 35 and have no family history of chromosomal disorders
- You have produced multiple high-quality embryos and want a faster, more affordable screen
- Your primary concern is identifying viable trisomies (Down syndrome being the most common)
- Time is a factor and you'd prefer faster results
PGT-A 24-chromosome is generally recommended if:
- You are over 35 (advanced maternal age increases risk of all aneuploidies, not just nine)
- You have a history of recurrent miscarriage or failed IVF cycles
- There is a family history of chromosomal rearrangements or microdeletion syndromes
- You have produced fewer embryos and want maximum information from each one
- You want the most comprehensive screen available
A note on "more is better"
It's tempting to think PGT-A 24-chromosome is always the smarter choice because it tests more. But a more sensitive test also returns more "abnormal" results — including mosaic embryos that may still produce healthy pregnancies.
The right test for you depends on your specific situation, and the conversation with your reproductive specialist matters more than choosing the most expensive option on the menu.
What about sex selection (also called gender selection)?
Both PGD FISH 9 and PGT-A 24-chromosome reveal the embryo's sex chromosomes (XX or XY), so both enable sex selection — sometimes called gender selection or family balancing.
However, the legality of non-medical sex selection varies significantly:
- Permitted in the United States, Mexico, Cyprus, and some other countries
- Prohibited in most of Western Europe (UK, Germany, France, Spain), Canada, India, and China
- Variable depending on circumstances in Ukraine, Georgia, and Armenia — your destination country's regulations apply
If sex selection is important to you, this should be discussed early in your consultation, as it may influence which destination country your coordinator recommends.
Key Takeaways
- Both tests are performed on day-5 trophectoderm biopsies — the procedure on the embryo is the same
- PGD FISH 9 screens 9 chromosome pairs using fluorescent probes; results in days, lower cost
- PGT-A 24-chromosome screens all 24 chromosomes using NGS; higher accuracy, detects microdeletions and mosaicism
- Both enable sex selection where legally permitted
- For couples over 35 or with prior IVF failures, PGT-A is generally recommended
- The right choice is a clinical conversation, not a price decision
This article is for educational purposes only and does not constitute medical advice. Genetic testing options, success rates, and legal availability of sex selection vary by clinic and country. Always discuss your specific situation with a qualified reproductive specialist before making decisions. Novaparent Surrogacy provides coordination services and works with licensed partner clinics in Ukraine, Georgia, and Armenia — your medical care is provided by the clinic's specialists.
Frequently asked questions
What is the difference between PGD and PGT-A?
PGD (Preimplantation Genetic Diagnosis), specifically PGD FISH 9, screens 9 chromosomes for major aneuploidies and X/Y chromosome composition. PGT-A (Preimplantation Genetic Testing for Aneuploidy) by NGS analyzes all 24 chromosomes (22 autosomes + X + Y) for any whole-chromosome aneuploidy, partial deletions, and duplications. PGT-A is the modern standard; PGD FISH 9 remains useful for specific cases.
Which test is more accurate, PGD FISH 9 or PGT-A 24-chromosome?
PGT-A 24-chromosome by NGS is more comprehensive and more sensitive — it screens all 24 chromosomes versus 9 for PGD FISH 9. PGT-A also detects mosaicism (mixed normal/abnormal cells) at higher resolution. However, "more accurate" depends on what you are testing for: PGD FISH 9 is sufficient and faster for couples whose only concern is the most common aneuploidies (Down syndrome, Patau, Edwards, Turner, Klinefelter) and family balancing.
How much does PGT-A cost in surrogacy in 2026?
PGT-A 24-chromosome by NGS typically costs $2,500–4,500 per cycle in 2026, with some Eastern European clinics offering it at $1,800–2,500. PGD FISH 9 is roughly $800–1,500 per cycle. Cost depends on number of embryos tested (most clinics charge per embryo with discounts above 4–5).
Do I need genetic testing if I am under 35?
Genetic testing is optional for women under 35 with no family history of chromosomal disorders. Aneuploidy rates are 20–30% under age 35, rising to 40–50% by age 38 and 60%+ by age 42. Testing is increasingly recommended for women 35+ and strongly advised for women 38+ to reduce miscarriage risk and time-to-baby.
Can PGT-A or PGD detect autism, intelligence, or eye color?
No. PGT-A and PGD FISH 9 detect chromosomal aneuploidies (extra or missing whole chromosomes) and large structural abnormalities. They do not analyze single-gene traits, polygenic conditions like autism risk, intelligence markers, or appearance traits. Polygenic embryo screening (PGT-P) is a separate emerging technology and is not offered in our partner clinics.
Is gender selection legal in Ukraine, Georgia, or Armenia?
Gender selection is legal in Ukraine for family balancing when medical indications exist. Georgia permits gender selection within IVF programs. Armenia has more conservative rules — gender selection is permitted only for medical reasons (sex-linked genetic disease prevention). Legal status can change; always confirm with your program coordinator before proceeding.
Can I do PGD FISH 9 first and then PGT-A on remaining embryos?
Generally not recommended. Each biopsy adds risk to the embryo (approximately 1–2% reduction in implantation rate per biopsy). Doing both tests sequentially means two biopsies on the same embryo, increasing damage risk. The standard approach is to choose one test upfront based on your medical and personal priorities.
How long does PGT-A take in 2026?
PGT-A by NGS typically returns results in 7–14 days from biopsy in 2026. PGD FISH 9 results return in 24–48 hours. Faster turnaround for FISH 9 is one reason it remains useful when speed matters (e.g., synchronized fresh transfer).
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