What Is Preimplantation Genetic Diagnosis (PGD)?
Preimplantation Genetic Diagnosis, often referred to as PGD or PGT-M (Preimplantation Genetic Testing for Monogenic disorders), is a game changer for intended parents. Used in conjunction with in vitro fertilization, PGD allows embryologists to test for specific genetic conditions before the embryos are transferred to a surrogate. For families with a known history of serious genetic disease or who just want to give their child the healthiest start possible, PGD is an essential part of the modern surrogacy process.
PGD is particularly valuable for single gene disorders such as cystic fibrosis, Tay-Sachs disease, and spinal muscular atrophy. These are conditions that can be passed down silently through generations, especially when both biological parents are carriers. Through early detection of these genetic disorders, families can make confident, informed choices.
As a U.S.-based surrogacy agency committed to ethical, supportive and medically sound assisted reproductive technology, Made in the USA Surrogacy ensures intended parents have access to the latest genetic testing technologies, whether looking for single gene mutations, chromosome abnormalities or serious genetic disease. When PGD is used effectively, it helps identify embryos that are free of genetic defects, giving families the best chance at a healthy, viable pregnancy.
How Does PGD Work?
In Vitro Fertilization: The Foundation of PGD
PGD only works with in vitro fertilization. Intended parents (or egg donors) undergo an IVF treatment cycle where eggs are retrieved, fertilized with sperm and cultured in specialized blastocyst culture systems. This process allows embryologists to monitor embryo development over several days, selecting embryos suitable for further testing.
By Day 5 or 6, embryos that reach the blastocyst stage are eligible for genetic testing, increasing the chances of selecting chromosomally normal embryos for transfer. These tested embryos give intended parents and surrogates peace of mind, particularly when the family has a known genetic disorder in their history.
The ability to assess embryos prior to transfer is one of the most critical advantages of PGD, especially for families going through fertility treatments after multiple failed implantation attempts or pregnancy loss.
Embryo Biopsy and Blastocyst Stage Testing
At the blastocyst stage, a few cells from the embryo’s outer layer, called the trophectoderm, are gently biopsied by an embryologist in a process called embryo biopsy. This specific procedure is called a blastocyst biopsy. Cells are carefully removed to provide genetic material for testing while the embryo, including its inner cell mass, remains viable and is cryopreserved for later transfer.
This biopsy is typically done on embryos prior to transfer to ensure the surrogate is only implanted with embryos suitable for pregnancy. This level of precision makes PGD an essential part of many advanced fertility treatments.
What Is a Blastocyst Biopsy? (And How Genetic Testing Is Performed)
A blastocyst biopsy involves extracting multiple cells when the embryo has fully developed, Day 5 or 6, after blastocyst culture. This yields more cells which improves the accuracy of detection for chromosomal abnormalities or single gene defects and reduces the risk of damaging a developing embryo. It’s the gold standard in reproductive medicine for selecting viable embryos linked to the highest chance of success.
Once biopsied, the sample undergoes advanced genetic testing using:
- Polymerase chain reaction (PCR) was used in early PGD to detect single gene mutations, including those responsible for single gene disorders like cystic fibrosis.
- Fluorescence in situ hybridization (FISH) has been largely replaced due to lower resolution but may still be used in limited applications.
- Array comparative genomic hybridization (aCGH) allows for high-resolution detection of whole-chromosome anomalies and smaller deletions or duplications.
- Next-Generation Sequencing (NGS) offers detailed information on mosaic embryos, single gene defects, and aneuploidy screening, with higher accuracy than older methods.
These technologies are designed to identify embryos with genetic abnormalities and distinguish between affected, carrier, and unaffected embryos. In some cases, all of this information can be obtained from a single biopsy taken from the same embryo, reducing the need for multiple testing rounds.
PGD is also referred to as preimplantation diagnosis, especially in clinical settings. When called preimplantation genetic screening (PGS or PGT-A), the focus is on identifying chromosomally normal embryos rather than targeting specific gene mutations. Both approaches may be used in tandem to improve outcomes.
Cleavage Stage Embryo Biopsy and Polar Body Biopsy
In some cases, clinics may perform cleavage stage biopsy (single cell removal at Day 3) on a cleavage stage embryo, or polar body biopsy which tests genetic material from unfertilized eggs. These methods may be used when blastocyst development is limited or when assessing maternal-only inherited conditions.
However, these alternatives are more prone to error, especially when the cell removed from the embryo may not represent the whole embryo accurately. In some cases, removing just one cell from a cleavage stage embryo could misclassify mosaic or viable embryos. While still part of the PGD toolkit, these methods are used with great caution.
Preimplantation Genetic Screening vs. Diagnosis
Some clinics refer to broader preimplantation genetic screening, often called PGS or PGT-A, to screen for chromosomal errors like aneuploidy. This is different from preimplantation diagnosis (PGD), which targets known single gene disorders such as cystic fibrosis.
While PGD zeroes in on a family history of specific genetic conditions, PGS helps assess overall embryo health by detecting issues like extra or missing chromosomes. Both techniques aim to identify embryos most likely to lead to a successful, healthy pregnancy.
PGD Benefits for Advanced Maternal Age & Recurrent Miscarriage Couples
Women in the advanced maternal age population or advanced maternal age couples, as well as those with a history of recurrent pregnancy loss, particularly benefit from PGD screening. Age-related chromosomal abnormalities, like Down syndrome, are more common and pregnancy rates from PGD cycles are higher with euploid embryo transfer compared to transfers without screening.
When used alongside PGS, PGD can help reduce the risk of miscarriage and improve the odds of selecting embryos suitable for long-term development. For intended parents, this is especially encouraging after failed fertility treatments or emotionally difficult losses.
Why Do Intended Parents Use PGD?
Reducing Genetic Disease & Achieving Healthy Pregnancy
PGD targets serious genetic disease and single gene mutations to transfer only unaffected embryos, avoiding chromosomally abnormal or affected embryo implantation. This is crucial when parents carry inherited genetic disordersor have a family history of single gene conditions.
Through genetic counseling and PGD, intended parents can understand their risk, test embryos accordingly, and dramatically reduce the chance of passing on a disorder like cystic fibrosis or sickle cell disease. This process helps identify embryos with the highest potential to lead to a healthy baby.### Reducing Multiple Pregnancies: Elective Single Embryo Transfer
After screening, clinics often recommend elective single embryo transfer (eSET) of one chromosomally normal, unaffected embryo, reducing the chance of multiple pregnancies and complications, especially among advanced maternal age couples. This helps the surrogate’s health and the chances of a viable pregnancy.
Intended parents may request gender-related testing, such as identifying male embryos, though this is usually only for medically indicated reasons or to balance inherited sex-linked diseases.
Increasing Success in IVF Treatment
PGD and PGS lead to higher implantation rates per embryo transfer with fewer transferred embryos, ultimately to successful pregnancy without repeated IVF cycles. That means a faster path to parenthood with less emotional stress, something every intended parent wants.
When done correctly, PGD ensures the embryos before transfer are the best candidates for success, both genetically and developmentally.
What Are the Risks and Limitations of PGD?
Medical Risks of Embryo Biopsy & Mosaic Embryos
While PGD improves selection accuracy, it has limitations:
- Mosaic embryos, with both normal cells and genetic abnormalities, are hard to classify with a single trophectoderm biopsy. Implanting mosaic embryos may lead to lower success rates or miscarriage.
- Cryopreservation loss: freezing and thawing can cause loss of viable embryos.
- Invasiveness: embryo biopsy, even with more cells removed at blastocyst stage, still has a small chance of causing damage or reducing embryo viability.
Not all parts of the same embryo may carry the same genetic material, so it’s possible to biopsy normal cells and still miss an underlying abnormality. That’s why accuracy and lab experience matter.
Ethical Considerations: Affected Embryos & Reproductive Medicine Ethics
Another consideration is when certain embryos are discarded. Some families disagree with selection for non-medical traits, such as sex, or for traits like intelligence. That’s why PGD should only be used for clear medical reasons, with genetic counseling, ethical guidance and individual values.
PGD Legal and Ethical Landscape in the U.S.
No Federal Oversight & Ethical Clinic Selection
While other countries require strict licensing, the U.S. has no federal laws governing PGD, so clinic selection and genetic counseling are key to ensure ethical and medically necessary use.
PGD vs Prenatal Diagnosis
Compared to PGD, prenatal diagnosis (amniocentesis and chorionic villus sampling) happens mid-pregnancy. PGD gives you the advantage of testing human preimplantation embryos before transfer, reducing emotional stress and reproductive risk.
How Much Does PGD Cost?
Breakdown & ART
Since PGD is part of assisted reproductive technology, the cost gets added to a standard IVF cycle. On average:
- PGD testing: $4,000–$10,000+
- Embryo biopsy (including blastocyst biopsy), freezing, thawing and embryo storage
- IVF meds, lab and professional/genetic counseling fees
Insurance may cover part of the cost if there is a known genetic risk, proof via letter of medical necessity and pre-authorization helps.
Frequently Asked Preimplantation Genetic Diagnosis (PGD) Questions
What is the difference between PGS and PGD?
PGS, now often called preimplantation genetic screening or PGT-A, checks for the number of chromosomes in an embryo. It’s used to screen for aneuploidy, extra or missing chromosomes, which can cause miscarriage or developmental conditions like Down syndrome.
PGD, on the other hand, stands for preimplantation genetic diagnosis. It’s used to diagnose specific genetic diseases like cystic fibrosis or Tay-Sachs disease, often based on a family history of those conditions. PGD uses advanced testing methods like PCR, FISH, aCGH or NGS to detect single gene mutations or inherited disorders in embryos before transfer.
Can PGD guarantee a healthy baby?
No. PGD can’t guarantee a healthy baby. While it reduces the risk of transferring embryos with known genetic disorders or chromosomal abnormalities, it can’t detect all potential conditions or developmental complications. Most clinics still recommend prenatal diagnosis later in the pregnancy, like amniocentesis or chorionic villus sampling, to confirm the health of the fetus.
PGD does however give intended parents more peace of mind by increasing the chances of selecting unaffected, chromosomally normal embryos before transfer.
Is elective single embryo transfer recommended after PGD?
Yes. Elective single embryo transfer (eSET) is often recommended especially for intended parents using PGD. By transferring only one chromosomally normal and genetically tested embryo you reduce the risk of multiple pregnancies which can increase medical complications for both the surrogate and baby.
For families using a surrogate, especially when using advanced fertility treatments, eSET with PGD is a safe and smart approach. It’s especially recommended for advanced maternal age couples or any case where embryo quality has been confirmed through testing.
How long does PGD take and what happens before embryo transfer?
PGD takes about 1-2 weeks from embryo biopsy to getting lab results. During this time the embryos are cryopreserved. Once the results are in, the intended parents along with their fertility team choose the embryo(s) for transfer.Embryo transfer happens in a separate cycle after testing is complete. The surrogate’s uterine lining is prepared through medication and once it’s ready the selected embryo is thawed and transferred during a timed procedure. This step is key to a healthy and viable pregnancy and is coordinated with your agency and medical provider.
Do all surrogates agree to PGD and embryo biopsy?
Not all surrogates are comfortable with every aspect of the fertility process, including genetic testing. At Made in the USA Surrogacy we ensure every surrogate is fully informed and consents to the medical protocols involved before being matched with intended parents. This includes embryo biopsy, preimplantation genetic testing and understanding how embryos are selected for transfer.
We believe open communication and aligned expectations between intended parents and surrogates is key to a smooth and ethical surrogacy journey.
Is PGD required for all surrogacy journeys?
No, PGD is not required. It’s a personal decision made by the intended parents in consultation with their fertility specialist. However, many intended parents choose PGD if they have a known genetic risk, are using donor eggs or sperm, or simply want to maximize their chances of a healthy, full-term pregnancy.
We help each family explore the pros and cons of PGD based on their unique background and goals. Whether you choose to pursue testing or not, our team will support you with guidance that respects your values.
Will PGD reduce our chances of having enough embryos?
It’s possible that PGD may reduce the number of embryos available for transfer, especially if only a few are chromosomally normal or free of inherited conditions. However, the goal is quality over quantity. Identifying embryos suitable for transfer increases the odds of a successful pregnancy and reduces the emotional and financial toll of failed cycles.
Many intended parents feel more peace of mind knowing that the embryos transferred have been thoroughly screened, even if the number of embryos is lower than expected.
Can PGD tell us the sex of our embryos?
Yes, PGD can identify the biological sex of each embryo as part of chromosomal screening. Some intended parents use this information to avoid passing on sex-linked genetic disorders, such as hemophilia, which primarily affects male embryos. Others may be curious about gender, but it’s important to use this technology ethically and in line with your clinic’s policies.
At Made in the USA Surrogacy, we focus on health first and foremost, and we encourage our families to make these decisions thoughtfully with the guidance of their fertility team.
Is PGD safe for the embryos?
When performed by experienced embryologists at a reputable clinic, PGD is generally considered safe. Blastocyst biopsy techniques used today are much more refined than earlier methods and remove cells from the outer layer, not the part of the embryo that becomes the baby.
That said, no procedure is entirely risk-free. There is a very small chance that the biopsy process or freezing/thawing can affect embryo viability. This is why it’s important to work with a clinic that specializes in PGD and has proven success rates.
How do we know if PGD is right for us?
This is one of the most important and personal questions you’ll face on your journey. PGD may be right for you if:
- You have a family history of genetic disorders
- You’ve had multiple miscarriages or failed IVF cycles
- You’re using donor eggs or sperm
- You want to reduce the risk of passing on inherited conditions
Our team will help you weigh your options with compassion and clarity, connect you with genetic counselors, and support you no matter what path you choose.
What happens if all of our embryos are chromosomally abnormal?
This is one of the more difficult outcomes that sometimes occurs during preimplantation genetic screening, especially for intended parents dealing with advanced maternal age or known fertility challenges. If all tested embryos are found to be chromosomally abnormal embryos, they are typically not recommended for transfer, as they carry a high risk of miscarriage or failed implantation.
While this can be heartbreaking news, it’s important to remember that PGD and PGS are designed to prevent even more difficult outcomes down the line, like pregnancy loss or severe health complications. If this happens, your fertility clinic may recommend another IVF cycle, donor eggs or sperm, or adjusting your treatment plan to increase the likelihood of producing healthy, viable embryos in the future.
We’re here to support you through these moments with compassion, transparency, and thoughtful next steps.
Will we have fewer embryos after PGD?
Possibly, yes, and that’s not necessarily a bad thing. One of the goals of PGD is to help you focus on quality over quantity. After testing, you may find that you have fewer embryos available for transfer than you originally started with. This happens when some embryos are found to be carriers of genetic conditions or chromosomally abnormal and therefore not suitable for transfer.
While the number of transferable embryos may go down, your overall chance of a successful, healthy pregnancy actually goes up, because you’re choosing from the embryos that have the highest potential to result in a live birth. Think of PGD as a process that helps you make smarter, more informed choices, even if the pool is smaller.
Our team works closely with your fertility clinic to manage expectations and ensure you’re never left navigating those results alone.
Can PGD help us avoid transferring chromosomally abnormal embryos?
Yes, absolutely, that’s one of the primary reasons many families choose PGD. By analyzing embryos before transfer, your fertility team can identify which ones are chromosomally abnormal embryos and exclude them from consideration. This significantly reduces the risk of miscarriage, failed cycles, or difficult decisions later in the pregnancy.
It’s especially helpful for couples with a history of failed IVF attempts, recurrent pregnancy loss, or known chromosomal risks. PGD takes the guesswork out of embryo selection, helping you feel more confident and in control of your family-building journey.
Is PGD for You?
Questions for Your Fertility Team
- What tests do you run? Array CGH? PCR? FISH?
- How do you handle mosaic embryos or chromosomal abnormalities?
- What percentage of human embryos remain viable after biopsy and cryopreservation?
- Can we do follow-up prenatal diagnosis for confirmation?
Collaboration with Your Surrogacy Agency
At Made in the USA Surrogacy, our team coordinates across fertility clinics, genetic labs and legal experts to ensure you balance medical safety, ethical judgment and emotional care at every stage, from single cell biopsy to successful pregnancy.
PGD for Intended Parents: Family Building
PGD has revolutionized IVF and reproductive medicine, especially when using a surrogate. By choosing only healthy embryos without genetic defects and chromosomal abnormalities, you minimize miscarriage risk, prevent severe genetic diseases and get a healthy singleton pregnancy. It’s a smart way to build your family.
Ready to use PGD for your journey?
Let us help you make informed, ethical decisions, protect your surrogate and grow your family.
