What is PGT

One of the most commonly asked questions by patients seeking fertility care is, “What is PGT”?

Preimplantation Genetic Testing (PGT), in conjunction with In Vitro Fertilization (IVF), aims to increase the likelihood of a successful pregnancy by identifying and transferring genetically normal embryos while decreasing the chances of transferring genetically abnormal embryos.

PGT has been proposed for various patient groups at risk of having genetically abnormal embryos, such as women of advanced maternal age (35 or older), those with a history of recurrent pregnancy loss (three or more), repeated failed IVF cycles with high-quality embryos (three or more transfers), and severe male factor infertility.

However, the use of PGT to test for genetic abnormalities in embryos has not consistently improved clinical outcomes and may even have some drawbacks. It has been reported that up to 16% of the results obtained through genetic analysis may be false positives, leading to the inadvertent discarding of embryos that could have resulted in a live birth.

One possible explanation for this phenomenon is embryo mosaicism, where an embryo contains both normal and abnormal cells. Sometimes, abnormal cell lines fail to proliferate, and the embryo can still develop into a normal offspring. If the biopsy for genetic testing is taken from an abnormal cell line, the embryo might be discarded, although it could have resulted in a healthy birth.

The application of PGT in specific cases, such as advanced maternal age, recurrent pregnancy loss, and repeated implantation failure, has not demonstrated clear benefits.

PGT has not shown a significant improvement in live birth rates for patients of advanced maternal age compared to the control group. Similarly, there is insufficient evidence for recurrent pregnancy loss and repeated implantation failure to support the use of PGT to improve outcomes.

PGT for male factor infertility has not been thoroughly studied, and there is not enough evidence to recommend its use for couples undergoing IVF with intracytoplasmic sperm injection (ICSI) due to male-factor indications.

PGT remains a personal choice for couples, particularly those without a history of repeated pregnancy losses. For these couples, PGT can be used to reduce the probability of miscarriage in IVF pregnancies.

PGT Procedure

Preimplantation Genetic Testing is a complex treatment consisting of the following steps:

1. In Vitro Fertilization to create embryos

2. Extended embryo culture to blastocyst

The embryos should reach the blastocyst stage (80 or more cells) by the fifth to seventh day after the egg retrieval.

The picture below shows an advanced stage of blastocyst development. Notice the central fluid-filled cavity. The cells within the blastocyst have already differentiated into the inner cell mass (at seven o’clock) that will give rise to the fetus and the trophectoderm cells that will form the future placenta.

3. Blastocyst trophectoderm (embryonic tissue) biopsy

An embryo biopsy is performed by creating an opening in the eggshell around the embryo. It is possible to safely remove six to eight cells through this opening using a special microscope with micromanipulators. The cells are taken from the trophectoderm only (future placenta cells, genetically identical to embryonic cells). The “inner mass” cells (embryonic cells) are not removed.

So far, there is no evidence that embryonic biopsy results in an increased chance of abnormalities in the baby or that the risk of birth defects is higher when compared to conceptions that occur spontaneously without medical assistance (2% to 5%).

4. Blastocyst vitrification (cryopreservation)

Since it takes several days to carry out the embryo genetic analysis, the blastocysts are cryopreserved immediately after their biopsy and stored in liquid nitrogen in our IVF laboratory.

5. Genetic analysis of the embryonic tissue

The accuracy of PGT cell analysis of genetically abnormal embryos approaches 100% but is not guaranteed. Even though highly unlikely, it is possible that an embryo tested as normal may not be genetically perfect.

6. Liquid nitrogen storage of the cryopreserved embryos

Vitrified embryos can be stored for extended periods, but most PGT patients will start an embryo transfer cycle with the onset of the first menstrual period after IVF treatment.

7. Subsequent Frozen Embryo Transfer

The endometrial lining is first stimulated with estrogen and progesterone, followed by the thawing of one or two embryos tested as normal by the PGT analysis and then transferring them inside the uterus.

Ultimately, PGT represents a valuable tool for identifying genetic abnormalities in embryos and can significantly benefit certain patient groups. However, it is essential to carefully consider its application and potential limitations, especially in cases where the benefits have not been clearly demonstrated.

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We look forward to meeting you at Bay IVF and, when your treatment is successful, celebrating your new pregnancy!


Years of Experience


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Hear from Our Patients’ Journey to Parenthood at Bay IVF!

I would highly recommend Bay IVF for those wanting to build their family and needing IVF support! Dr. Polansky and the whole Bay IVF team were so supportive and welcoming while also honest and realistic. Our girl is our dream come true!

Jennifer C.-F.

This clinic has been amazing to work with. All the nurses and staff made sure I was always comfortable and were there to answer questions any time I needed. We are incredibly grateful to Dr. Polansky and the team for everything they did for us.

Harpreet K.

Words could never express the gratitude my husband and I will always have for Bay IVF! We did our research and decided to check out Bay IVF. We scheduled a consultation and felt an instant connection… love at first sight!

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Meet Your Doctor

  • Dr. Polansky received his medical diploma from Charles University in Prague, the Czech Republic, in 1978.
  • After completing his OB/GYN residency at Jewish Hospital in Saint Louis, MO, he graduated from the Reproductive Endocrinology and Infertility (REI) fellowship at Stanford University in 1985.
  • In the same year, he co-founded the Stanford IVF Clinic.
  • Dr. Polansky obtained board certification in Obstetrics and Gynecology in 1986 and became REI subspecialty board certified in 1988.
  • In 1987, he left Stanford University and established Nova IVF.
  • In 2011, he founded Bay IVF, where he provides advanced fertility treatments with a holistic approach, utilizing state-of-the-art techniques.
  • Dr. Polansky personally performs ultrasound examinations, egg retrievals, embryo transfers, and ovarian and endometrial stimulations for his patients.
  • He is deeply committed to his patients and freely shares his cell phone number, ensuring accessibility and availability 24/7.

Frank Polansky, M.D.

Dr. Polansky’s Communication With Patients

Real texts, anonymous patient names

Initial Appointment Questions

When you call to schedule your consultation, Erica will ask you a short series of questions regarding your reproductive history.

  • Your name
  • Your date of birth
  • Your height
  • Your weight
  • Do you know which treatment you plan to have?
  • How many times have you been pregnant?
  • For each of your pregnancies, what was the conception date? (month and year)
  • What was the outcome?
  • Were the pregnancies with your current partner?
  • If known, what is the cause of your infertility?
  • What is your average cycle length? (number of days between onsets of your periods)
  • Are you currently taking any medications? If yes, which ones?
  • Are you allergic to any medications? If yes, which ones?
  • Your partner’s name (if applicable)
  • Your partner’s date of birth (if applicable)
  • What is the length of your relationship with your current partner? (years and months)
  • When was the last time either of you used any contraception?
  • Is the male partner currently taking any medications? If yes, which ones?
  • Is the male partner allergic to any medications? If yes, which ones?
  • What is the total number of pregnancies the male partner has ever caused?
  • Has the male partner ever caused a pregnancy without the ICSI (Intracytoplasmic Sperm Injection) procedure?
  • Has the male partner had a vasectomy or vasectomy reversal?
  • If available, for each Semen Analysis, please give the date (day, month, and year), volume, concentration (sperm count), percentage of motile sperm, and percentage of morphologically normal sperm.
  • Have you ever had any treatment for, or problems with, your lungs, heart, blood and blood vessels, breasts, digestive system, genito-urinary system, thyroid disease, diabetes, or neurological disorder? (female partner only)
  • For each X-ray of your uterus and Fallopian tubes (hysterosalpingogram), laparoscopy, hysteroscopy, or laparotomy, please give the procedure date (day, month, and year) and the findings.
  • If available, for each FSH, LH, estradiol (estrogen, E2), and AMH (Anti-Mullerian Hormone) test you have had, please give the date of the test (day, month, and year) and the result.
  • Have you done any intrauterine inseminations (IUI)? If yes, how many?
  • Have you had ovarian stimulation with injectable medications?
  • For each IVF treatment you have had, please provide the following information if available: Date (month and year), the dose of medications to stimulate your ovaries, your highest estrogen level, number of ovarian follicles that developed, number of eggs retrieved, whether ICSI was done, number of embryos available, number of embryos transferred, number of embryos frozen, and the treatment outcome.
  • Have you ever smoked cigarettes? If yes, how many cigarettes a day during the last three months? (Please remember that you must not smoke during your treatment.)

This is Erica

She will be providing you with exceptional support throughout your treatment journey at Bay IVF.

Listen to a typical conversation between Erica and a new patient.

Patients’ Thank You Cards

Your Initial Visit at Bay IVF

Attending a new patient appointment at a fertility clinic can be stressful. Our primary objective is to ensure that your initial visit is friendly and relaxing. We encourage you to ask questions at every step of the process.

1 — When You Arrive

You will be welcomed by one of the clinic receptionists. One of our nurses will measure your height and weight and take your blood pressure

2 — Meet Your Doctor

Dr. Polansky will ask you a series of clarifying questions and then provide you with a summary of the factors contributing to your infertility

4 — Exam Room

One of the nurses will escort you to an examination room. Your examination will begin with listening to your lungs and heart

3 — Ask Your Questions

You will then have a discussion with him about the most suitable reproductive treatment(s) for you. During this time, you will have the opportunity to ask any questions you may have

5 — Ultrasound of the Ovaries

The next step is a pelvic ultrasound to examine the uterus and ovaries. This ultrasound will help determine the number of antral follicles present within the ovaries

6 — Financial Part

Following that, you will have a discussion with one of the financial advisors regarding the financial aspects of your treatment, including potential treatment financing options

8 — Support 24/7

If you have any questions after leaving the clinic, please feel free to reach out to us via phone call, text, or email. Open and discreet communication is an integral part of the care we provide at Bay IVF

7 — What About Time?

Your entire visit is expected to last approximately one hour

Schedule Your Initial Consultation With Dr. Polansky

Online or In-Person

You can also complete the form below to request your initial consultation

    Next Step: One of our coordinators will call you for information about your reproductive history. See the questions they will ask on Our First Phone Call

    Still Have Questions?

    We know this is a big decision. It is important for us that you feel really comfortable.