Third Generation IVF (PGD/PGS) Complete Guide: Do You Need It?
Comprehensive guide to PGD/PGS genetic testing in IVF: how it works, who needs it, what it screens for, costs, and common misconceptions.
"My doctor recommended 3rd generation IVF — is it really necessary?"
This is one of the most common questions we receive. Let's break down everything you need to know about PGD/PGS genetic testing in IVF.
What Is Third Generation IVF?
| Generation | Formal Name | Core Technology | Solves |
|---|---|---|---|
| 1st Gen | Conventional IVF | Natural fertilization | Female tubal issues |
| 2nd Gen | ICSI | Single sperm injection | Male factor infertility |
| 3rd Gen | PGT | Embryo genetic testing | Genetic diseases + chromosomal abnormalities |
PGT (Preimplantation Genetic Testing) has three subtypes:
- PGT-A (formerly PGS): Screens for chromosome number abnormalities
- PGT-M (formerly PGD): Detects single gene disorders
- PGT-SR: Detects structural chromosome rearrangements
Who Should Consider PGT?
Strongly Recommended for PGT-A:
- Women aged 35+: Chromosomal abnormality rates increase sharply after 35
- Recurrent implantation failure: 2+ failed transfers with good embryos
- Recurrent miscarriage: 2+ unexplained pregnancy losses
- Severe male factor: May affect embryo chromosomes
- Efficiency-focused: Don't want to waste time on abnormal embryos
Required for PGT-M:
- Known genetic disease carriers: Such as thalassemia, hemophilia
- Previous child with genetic disease: To prevent transmission
- HLA matching needs: For sibling donor compatibility
What Can PGS Screen?
PGS examines all 23 chromosome pairs, detecting:
- Numerical abnormalities: Trisomies (e.g., Down syndrome), monosomies
- Deletions and duplications: Missing or extra chromosome segments
- Mosaicism: Some cells with chromosomal abnormalities
Treatment Process
The process adds genetic testing steps to standard IVF:
- Pre-treatment assessment
- Ovarian stimulation
- Egg retrieval + ICSI fertilization
- Blastocyst culture (Day 5-6)
- Biopsy: 5-10 trophectoderm cells sampled
- Genetic analysis: Results in 7-14 days
- Embryo cryopreservation during testing
- Transfer of selected healthy embryo
Common Misconceptions
"3rd gen is better than 2nd gen"
Wrong. They address different problems. If you only have tubal issues or mild male factor, 2nd gen IVF is perfectly adequate.
"PGS guarantees success"
Wrong. PGS ensures normal chromosomes, but uterine factors and immune issues can still cause failure.
"Biopsy harms the embryo"
Research shows trophectoderm biopsy (the part that becomes placenta) does not affect embryo development or baby health.
FAQ
Q: Can I do 3rd gen IVF in my home country?
A: Availability varies by country. In China, strict medical indications are required. Thailand has no such restrictions, making it accessible to anyone who wants genetic screening.
Q: How long do results take?
A: Typically 7-14 business days. Embryos are frozen during this period.
Not sure if you need PGD/PGS? Contact AddBaby — our medical advisors can review your reports and provide professional guidance.
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