Preimplantation Genetic Testing (PGT)

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Preimplantation Genetic Testing (PGT) is an advanced laboratory procedure performed during an IVF cycle to examine embryos for chromosomal abnormalities or specific genetic disorders before embryo transfer. The test helps fertility specialists identify embryos with the highest potential for a healthy pregnancy, reducing the risk of miscarriage and certain inherited conditions.

PGT is performed after fertilisation when embryos have developed to the blastocyst stage. A few cells are carefully collected from the embryo and analysed in a specialised genetics laboratory. Based on the results, embryos with normal genetic findings may be selected for transfer. It doesn’t change how IVF works at its core; egg retrieval, fertilisation, and embryo development still happen the same way. What PGT adds is an extra layer of information, helping your fertility team identify which embryos are most likely to result in a healthy, ongoing pregnancy.

Unlike traditional prenatal testing, which is performed during pregnancy, PGT is conducted before pregnancy begins, allowing intended parents and fertility specialists to make informed decisions regarding embryo selection.

This page walks you through everything — what PGT is, the different types available, who it’s typically recommended for, how the procedure fits into your IVF cycle, what it costs in India, and the realistic success rates you can expect. Our goal is simply to help you understand your options clearly so that any decision you make feels informed rather than overwhelming.

What is Preimplantation Genetic Testing (PGT)?

Preimplantation Genetic Testing is a screening procedure performed on embryos created through IVF before one of them is selected for transfer. A small number of cells are carefully removed from the embryo, usually at the blastocyst stage, around day five or six of development, and sent to a specialised genetics laboratory for analysis. The lab examines these cells for chromosomal abnormalities or specific inherited genetic conditions, depending on the type of PGT being performed. The embryo itself continues to be safely frozen while results are awaited, and the actual embryo transfer happens in a later, separate cycle once the results are available.

How PGT Helps Select Genetically Healthy Embryos

Not every embryo that looks healthy under a microscope is necessarily chromosomally normal. In fact, chromosomal abnormalities become more common as a woman ages, and they’re a significant reason why some embryos fail to implant or why some pregnancies end in early miscarriage. PGT allows embryologists to look beyond outward appearance and assess the genetic makeup of each embryo. This means that instead of choosing an embryo for transfer based purely on how it looks on day five, your fertility specialist can prioritise embryos that have also been confirmed to have a normal chromosomal count, which is associated with better implantation potential and a lower risk of pregnancy loss.

Difference Between Embryo Screening and Embryo Diagnosis

These two terms are often used loosely, but they mean slightly different things. Embryo screening (as in PGT-A) looks broadly at the number of chromosomes in an embryo to check whether there are too many or too few, without targeting any single, specific disease. Embryo diagnosis (as in PGT-M) is more targeted: it tests for a specific, known genetic mutation that runs in the family, such as thalassaemia or cystic fibrosis. Understanding this distinction helps clarify why your doctor may recommend one type of PGT over another, depending on your personal and family medical history.

Why is Preimplantation Genetic Testing Recommended?

PGT isn’t recommended for every IVF patient as a routine step. Rather, it’s typically suggested in situations where the additional information it provides is likely to meaningfully change treatment decisions or improve outcomes. Here’s why fertility specialists consider it valuable in the right circumstances.

Reducing the Risk of Genetic Disorders

For couples who carry a known genetic mutation or have a family history of an inherited condition, PGT-M offers a way to identify embryos that have not inherited that specific condition, before pregnancy even begins.

Improving Embryo Selection During IVF

When multiple embryos are available, PGT gives the embryology team an additional, objective layer of information to work with — beyond the visual grading used in standard IVF — to help identify which embryo is most likely to lead to a successful pregnancy.

Lowering the Chances of Miscarriage

A significant proportion of early miscarriages are linked to chromosomal abnormalities in the embryo. By identifying and avoiding the transfer of embryos with these abnormalities, PGT-A may help reduce the likelihood of miscarriage in certain patient groups, particularly those with a prior history of pregnancy loss.

Enhancing IVF Success Rates

While PGT does not guarantee pregnancy, transferring an embryo that has been confirmed as chromosomally normal is associated with improved implantation rates per transfer in many studies, particularly relevant for women in certain age groups or with a history of repeated implantation failure.

Supporting Healthier Pregnancies

Ultimately, the goal of PGT is to support a smoother, more confident path toward a healthy pregnancy and baby by reducing some of the uncertainty that comes with embryo selection, particularly for couples who have already faced disappointment during their fertility journey.

Preimplantation Genetic Testing for Aneuploidy

Types of Preimplantation Genetic Testing (PGT)

PGT isn’t a single test — it’s a category of related techniques, each designed to look for a different kind of genetic concern. Your fertility specialist will recommend the type that’s relevant to your specific medical and family history.

PGT-A (Preimplantation Genetic Testing for Aneuploidy)

PGT-A is the most commonly performed type of preimplantation genetic testing. It screens embryos for aneuploidy, meaning an abnormal number of chromosomes, where an embryo has either extra or missing chromosomes instead of the typical 46.

What Does PGT-A Detect?

PGT-A checks all 23 pairs of chromosomes in an embryo, identifying conditions where there’s an extra or missing chromosome, such as Down syndrome (an extra chromosome 21) or Turner syndrome (a missing X chromosome). It does not look at individual genes within those chromosomes.

Who Should Consider PGT-A?

PGT-A is generally considered for women of advanced maternal age, couples who have experienced recurrent miscarriages, those who have had multiple unsuccessful IVF cycles, and couples who simply want additional information to support embryo selection when several good-quality embryos are available.

PGT-M (Preimplantation Genetic Testing for Monogenic Disorders)

PGT-M, sometimes still referred to by its older name PGD, is used when one or both partners are known carriers of a specific single-gene (monogenic) genetic condition. Unlike PGT-A, this test is highly targeted — the lab specifically looks for the exact mutation already identified in the family.

What Genetic Diseases Can Be Identified?

PGT-M can be used to test for conditions such as thalassaemia, sickle cell disease, cystic fibrosis, spinal muscular atrophy, and various other inherited single-gene disorders — provided the specific mutation has already been identified through prior genetic counselling and carrier testing.

Who Benefits from PGT-M?

This test is most relevant for couples who are known carriers of a specific inherited condition, those with a family history of a genetic disease, or couples who have previously had a child affected by a diagnosed monogenic disorder and want to reduce the chance of it happening again.

PGT-SR (Preimplantation Genetic Testing for Structural Rearrangements)

PGT-SR is designed for situations where one partner carries a structural rearrangement in their chromosomes — meaning the chromosomes are made up of the correct genetic material, but pieces are arranged differently than usual.

Understanding Chromosomal Rearrangements

Common examples include translocations (where a segment of one chromosome has attached to another) or inversions (where a segment of a chromosome is flipped). People with these rearrangements are often healthy themselves but may be more likely to pass on chromosomally unbalanced embryos, which can contribute to recurrent miscarriage or failed implantation.

Who Should Consider PGT-SR?

PGT-SR is typically recommended for couples where one partner has been found, through blood karyotyping, to carry a known balanced translocation or inversion — often discovered during an infertility workup or after recurrent pregnancy loss.

Who Should Consider PGT Testing?

While your fertility specialist will make a personalized recommendation based on your specific history, PGT testing is generally most relevant for couples in the following situations.

Couples with Recurrent Miscarriages

If you’ve experienced two or more pregnancy losses, your doctor may suggest PGT-A to help identify chromosomally normal embryos, which may reduce the likelihood of another loss linked to chromosomal causes.

Women of Advanced Maternal Age

As maternal age increases — particularly from the mid-to-late thirties onward — the proportion of embryos with chromosomal abnormalities tends to rise. PGT-A can help identify the embryos most likely to be chromosomally normal among those available.

Couples with Multiple Failed IVF Cycles

If previous embryo transfers have not resulted in a successful pregnancy and faced IVF failure despite seemingly good-quality embryos, PGT-A may offer additional insight into whether undetected chromosomal issues were a contributing factor.

Individuals with Known Genetic Disorders

If you or your partner are aware of carrying a specific inherited genetic condition, PGT-M allows embryos to be tested specifically for that mutation before transfer.

Couples with a Family History of Inherited Conditions

Even without a personal diagnosis, a strong family history of a specific genetic disease may prompt your doctor to recommend genetic counselling, which can determine whether PGT-M is appropriate for your situation.

Male Partners with Chromosomal Abnormalities

Certain male fertility issues, including some cases of severe male factor infertility, are sometimes linked to chromosomal abnormalities such as translocations. In these cases, PGT-SR may be recommended alongside ICSI.

How Does PGT Work with IVF?

Role of IVF in PGT Testing

PGT is not a standalone procedure — it is always performed as part of an IVF cycle. The eggs and sperm must first be brought together to create embryos in the laboratory before any genetic testing can take place.

Why PGT Cannot Be Performed Without IVF

Since PGT involves examining cells taken directly from a developing embryo, it inherently requires embryos to exist outside the body in a laboratory setting. This is only possible through IVF (or IVF combined with ICSI), which is why PGT is always offered as an add-on to an IVF cycle rather than a separate, independent test.

Embryo Development Before Genetic Testing

After fertilization, embryos are cultured in the laboratory for several days. At Nimaaya, we prefer to perform the biopsy for genetic testing at the blastocyst stage, around day five or six of development, because the embryo has more cells at this point, allowing a small biopsy sample to be taken with less relative impact on the embryo.

What is the PGT Procedure?

Here is a clear, step-by-step look at how PGT fits into a complete IVF cycle, from your very first consultation through to embryo transfer.

Initial Fertility Consultation and Evaluation

Your journey begins with a detailed discussion of your medical history, any previous fertility treatments, and the specific reason PGT is being considered. Depending on your situation, this may include a referral for genetic counselling, particularly if PGT-M or PGT-SR is being considered.

Ovarian Stimulation

The female partner undergoes a course of hormone injections, typically over 10 to 14 days, to stimulate the ovaries to develop multiple mature eggs. Regular monitoring through ultrasound and blood tests allows the team to track progress and adjust medication as needed.

Egg Retrieval Procedure

Once the eggs are mature, a minor procedure called egg retrieval (or ovum pick-up) is performed under sedation. A fine needle is used, under ultrasound guidance, to collect the eggs from the ovarian follicles.

Fertilisation Through IVF or ICSI

The retrieved eggs are fertilized in the laboratory, either through conventional IVF or through ICSI (Intracytoplasmic Sperm Injection), depending on sperm quality and other clinical factors. Many clinics prefer ICSI when PGT is planned, as it reduces the risk of sperm DNA contaminating the biopsy sample.

Embryo Culture to Blastocyst Stage

Fertilised eggs are carefully cultured in the lab for five to six days, during which the embryology team monitors their development and growth toward the blastocyst stage.

Embryo Biopsy

A small number of cells — usually from the outer layer of the blastocyst, called the ‘trophectoderm’ — are gently removed using specialised micromanipulation equipment. This outer layer eventually forms the placenta, not the baby itself, which is part of why this approach is considered to have a relatively low impact on the embryo’s core developmental potential.

Genetic Testing and Analysis

The biopsied cells are sent to a specialized genetics laboratory, where techniques such as Next Generation Sequencing (NGS) are used to analyze the chromosomal or genetic makeup of each embryo.

Cryopreservation of Embryos

While waiting for genetic results — which usually takes one to two weeks — all biopsied embryos are safely frozen through a process called vitrification. This pause is necessary and does not harm the embryo’s future potential.

Selection of Genetically Normal Embryos

Once results are available, your fertility specialist reviews them with you and identifies which embryo(s) are chromosomally normal (or unaffected, in the case of PGT-M) and therefore suitable for transfer.

Frozen Embryo Transfer (FET)

In a separate, subsequent cycle, the uterine lining is prepared with medication, and the selected embryo is thawed and transferred into the uterus — a relatively simple procedure that doesn’t require anaesthesia.

Step-by-Step PGT Treatment Timeline

Week 1–2: Ovarian Stimulation

The cycle begins with daily hormone injections to stimulate the ovaries, alongside regular monitoring visits to track follicle growth.

Egg Retrieval and Fertilisation

Around day 12 to 14, egg retrieval is performed, followed immediately by fertilisation in the laboratory later that same day.

Embryo Biopsy and Genetic Screening

By day five or six after fertilisation, embryos that have reached the blastocyst stage undergo biopsy, and the cell samples are sent for genetic analysis.

Embryo Freezing and Result Processing

All biopsied embryos are frozen the same day as the biopsy. Genetic results are typically available within one to two weeks, depending on the laboratory and the complexity of testing required.

Frozen Embryo Transfer Cycle

Once results confirm which embryo(s) are suitable, a separate FET cycle is planned – usually beginning in the next menstrual cycle or the one after, depending on your body’s readiness and your doctor’s recommendation.

Benefits of Preimplantation Genetic Testing

Improved embryo selection

provides objective genetic information beyond visual appearance alone, supporting more informed decisions about which embryo to transfer.

Increased implantation rates

Transferring a chromosomally normal embryo is associated with a higher chance of successful implantation per transfer in many patient groups.

Reduced risk of miscarriage

By identifying and avoiding embryos with chromosomal abnormalities, some early pregnancy losses linked to genetic causes may be prevented.

Lower risk of chromosomal abnormalities

Particularly relevant for couples concerned about conditions such as Down syndrome, especially with advancing maternal age.

Reduced chances of passing inherited diseases

PGT-M specifically helps couples avoid transferring embryos affected by a known monogenic condition running in the family.

Better pregnancy outcomes

By reducing some sources of uncertainty in embryo selection, particularly for couples with a complicated fertility history.

Confidence during the IVF journey

Many couples find that having additional genetic information, even when it doesn’t guarantee an outcome, helps them feel more informed and prepared for each step.

Risks and Limitations of PGT

PGT is a valuable tool, but it isn’t without limitations. Being aware of these helps set realistic expectations before you begin.

Embryo Biopsy Risks

While modern biopsy techniques are designed to minimize impact, there is a small theoretical risk associated with removing cells from any embryo. Experienced embryologists work specifically to reduce this risk through careful technique and appropriate timing.

Possibility of Mosaic Embryos

Some embryos contain a mixture of normal and abnormal cells — a phenomenon called mosaicism. These results can be more complex to interpret, and your fertility specialist will discuss what a mosaic result means for your specific embryo and whether it may still be considered for transfer in certain circumstances.

False Positive or False Negative Results

Like any laboratory test, PGT is highly accurate but not entirely infallible. In rare cases, a result may not perfectly reflect the embryo’s true genetic status, which is one reason why prenatal testing during pregnancy is still recommended even after a PGT-tested embryo is transferred.

Not All Genetic Disorders Can Be Detected

PGT-A and PGT-SR look at chromosomal structure, while PGT-M looks only for a specific, pre-identified mutation. None of these tests can screen for every possible genetic or developmental condition, and PGT does not replace standard prenatal screening during pregnancy.

Additional Cost and Treatment Time

Because PGT requires a separate genetic laboratory, additional embryology time, and typically a frozen embryo transfer in a later cycle rather than a fresh transfer, it does add to both the overall cost and the total treatment timeline compared to standard IVF alone.

Emotional Considerations

Waiting for genetic results can be an anxious time, and in some cases, couples may learn that fewer embryos are suitable for transfer than they had hoped. Having support — whether from your partner, a counsellor, or your care team — during this waiting period can make a meaningful difference.

PGT Success Rates

How PGT Improves IVF Outcomes

PGT itself does not get anyone pregnant — what it does is help identify which embryo, among those available, has the best chromosomal profile for transfer. In appropriately selected patients, this can translate into a higher likelihood of implantation per embryo transferred, and in some cases, fewer transfers needed to achieve a successful pregnancy.

Factors Affecting PGT Success Rates

Several factors influence how much of a difference PGT makes for a given couple, including the number of embryos available for testing, the underlying reason PGT was recommended, and the overall health of the uterine environment receiving the embryo.

Maternal Age and Embryo Quality

Maternal age remains one of the most significant factors in fertility outcomes generally. Younger women tend to produce a higher proportion of chromosomally normal embryos, while women of advanced maternal age may have fewer normal embryos among those tested — which is precisely why PGT-A is often most valuable in this group, helping to avoid the transfer of an abnormal embryo that would be unlikely to succeed.

Importance of Laboratory Expertise

The accuracy of embryo biopsy and the reliability of genetic results depend heavily on the skill of the embryology team and the quality of the genetics laboratory used. Choosing a fertility centre with established embryology expertise and a trusted genetic testing partner is an important part of getting dependable results.

Is PGT Testing 100% Accurate?

This is one of the most important questions to understand clearly: no genetic test, including PGT, is 100% accurate, and it’s important to approach this technology with realistic expectations rather than viewing it as a guarantee.

Accuracy of PGT-A

PGT-A using modern techniques such as next-generation sequencing is highly accurate at detecting chromosomal abnormalities, but a small margin of error does exist, partly due to the complexity of interpreting biopsy samples and the possibility of mosaicism within the embryo.

Accuracy of PGT-M

PGT-M, when testing for a specific, well-characterized mutation that has already been confirmed in the family through genetic counselling, tends to be very accurate for that particular condition — though it is specific to the mutation tested and does not screen for unrelated genetic conditions.

Understanding the Limitations of Genetic Testing

Because of this small margin of uncertainty, doctors continue to recommend standard prenatal screening and diagnostic tests during pregnancy, even after a PGT-tested embryo has been transferred and a pregnancy has been confirmed. PGT is best understood as a tool that significantly improves the odds of selecting a healthy embryo — not as an absolute guarantee of a healthy baby.

PGT-A Cost in India

Average Cost of PGT Testing

The cost of PGT in India varies depending on the clinic, the type of PGT performed, and the number of embryos tested. As a general guide, PGT-A typically adds a noticeable cost on top of a standard IVF cycle, reflecting the additional embryology biopsy work and the separate genetic laboratory analysis involved. Because pricing differs between clinics and patient circumstances, it is best to request a personalised, itemised estimate during your consultation rather than relying on general figures found online.

PGT Cost as Part of an IVF Cycle

It’s worth understanding that the cost of PGT is almost always layered on top of — not instead of — the base cost of an IVF cycle. Your total expense includes the standard IVF process (stimulation, retrieval, fertilisation, culture) plus the additional biopsy and genetic testing fees, and typically a separate frozen embryo transfer cycle as well.

Cost of Testing Multiple Embryos

Most genetics laboratories charge a base fee for setting up the test, plus a per-embryo fee for each additional embryo tested. This means that if you have several good-quality embryos available, testing all of them will cost more than testing just one or two, but it also gives you more information about your full cohort of embryos.

Factors Affecting PGT Test Cost

Type of PGT Performed

GT-M and PGT-SR tend to involve more customised laboratory work than PGT-A, since they require developing or using a specific genetic probe for the family’s particular mutation or rearrangement, which can affect overall pricing.

Number of Embryos Tested

As mentioned, cost generally scales with the number of embryos sent for testing, since each embryo requires an individual biopsy and laboratory analysis.

IVF and ICSI Requirements

Since PGT is always combined with an IVF cycle (often using ICSI to reduce contamination risk during biopsy), the underlying IVF/ICSI costs form a significant part of your overall treatment expense.

Laboratory Technology Used

Clinics partnering with advanced genetics laboratories using modern techniques like Next Generation Sequencing may have different pricing structures compared to those using older testing methods.

Fertility Centre Expertise

The experience level of the embryology team performing the biopsy, and the clinic’s overall track record with PGT cycles, can also be reflected in the overall cost and the value you receive from the procedure.

Additional Fertility Procedures

If your treatment plan includes other elements — such as surgical sperm retrieval, donor gametes, or multiple frozen embryo transfer attempts — these will add to your total cost beyond the PGT testing itself.

PGT vs PGD vs PGS: Understanding the Terminology

Why PGD and PGS Terms Were Replaced

If you’ve researched this topic before, you may have come across the older terms PGD (Preimplantation Genetic Diagnosis) and PGS (Preimplantation Genetic Screening). These terms were used for many years, but as the field of reproductive genetics matured, professional bodies recognized the need for clearer, more standardized terminology to avoid confusion between testing for specific diseases versus broader chromosomal screening.

Current International Classification of PGT

Today, the umbrella term PGT (Preimplantation Genetic Testing) is used internationally, with three specific subtypes: PGT-A (what used to be called PGS, for chromosomal screening), PGT-M (what used to be called PGD, for specific monogenic disorders), and PGT-SR (for structural chromosomal rearrangements). If your doctor or an older article uses the terms PGD or PGS, they are generally referring to what is now classified under the PGT umbrella.

Frequently Asked Questions About PGT

Is PGT Necessary for Every IVF Patient?

No, PGT is not necessary or recommended for every IVF patient. It is generally suggested in specific situations — such as advanced maternal age, recurrent miscarriage, repeated implantation failure, or a known genetic condition in the family. Your fertility specialist can help you understand whether it’s likely to be beneficial in your particular case.

Can PGT Prevent Genetic Disorders?

PGT can help identify embryos affected by a specific known genetic condition (PGT-M) or by chromosomal abnormalities (PGT-A/PGT-SR) before transfer, which can reduce the chance of that particular condition being passed on. However, it cannot screen for every possible genetic or developmental condition that may affect a baby.

Does PGT Guarantee Pregnancy?

No. PGT improves the information available for embryo selection, but it does not guarantee implantation or a successful pregnancy. Many other factors — including uterine receptivity, hormonal balance, and overall health — also play an important role in whether a pregnancy is achieved and continues successfully.

Is PGT Safe for Embryos?

The biopsy technique used in PGT is performed by trained embryologists using specialized equipment, and current evidence broadly supports its safety when performed by experienced professionals. As with any laboratory procedure involving embryos, a small theoretical risk exists, which your embryology team works carefully to minimize.

Can PGT Detect All Genetic Conditions?

No single PGT test can detect every possible genetic condition. PGT-A looks at chromosome number, PGT-SR looks at chromosomal structure, and PGT-M looks only for a specific, pre-identified mutation. None of these replace comprehensive prenatal testing during pregnancy.

How Long Does It Take to Get PGT Results?

Genetic results are typically available within one to two weeks after the embryo biopsy, though this can vary slightly depending on the laboratory and the type of testing being performed.

Can PGT Reduce Miscarriage Risk?

For couples whose previous miscarriages were linked to chromosomal causes, selecting a chromosomally normal embryo through PGT-A may help reduce the risk of another loss for that specific reason. However, miscarriage can occur for many reasons unrelated to embryo chromosomes, so PGT cannot eliminate this risk entirely.

Is PGT Suitable After Failed IVF Cycles?

PGT-A is often considered after multiple unsuccessful IVF cycles, particularly when the reason for previous failures is unclear. It can help determine whether chromosomal abnormalities in the embryos may have been a contributing factor, which can guide the approach for subsequent attempts.

Why Choose Nimaaya IVF Centre for PGT Testing?

Experienced Fertility Specialists

At Nimaaya, your treatment is guided by fertility specialists who take the time to understand your complete history and explain whether PGT is genuinely relevant to your situation — rather than recommending it as a default add-on.

Advanced Embryology and Genetic Screening Support

Our embryology team works with established genetic testing partners to ensure that embryo biopsies are performed with care and that results are interpreted accurately and explained to you in plain language.

Personalised Fertility Treatment Plans

Every couple’s fertility history is different, and your treatment protocol — including whether PGT is recommended, and which type — is tailored specifically to your diagnostic findings and personal circumstances.

High Standards of Patient Care

We understand that waiting for genetic results, and the broader IVF journey itself, can be an emotionally demanding experience. Our team is committed to clear communication and compassionate support at every stage of your treatment.

Comprehensive IVF and Genetic Testing Services Under One Roof

From your initial consultation through ovarian stimulation, egg retrieval, fertilization, embryo biopsy, and eventually frozen embryo transfer, Nimaaya Fertility Centre offers integrated care so you don’t have to coordinate between multiple, disconnected providers during this important journey.

If you’d like to understand whether Preimplantation Genetic Testing is appropriate for your specific fertility journey, we’d encourage you to book a consultation with our team. Together, we can review your history, answer your questions honestly, and help you decide on the path that feels right for you

For couples considering Preimplantation Genetic Testing (PGT) as part of their IVF journey, Nimaaya offers expert-led fertility care backed by advanced reproductive technology and evidence-based practices. Available in Surat, Vadodara, and Ahmedabad, our experienced fertility specialists and embryology team use PGT to help identify chromosomally healthy embryos before transfer, supporting informed treatment decisions and improving the chances of a healthy pregnancy.

At Nimaaya, every recommendation for PGT is made after a thorough evaluation of your medical history, fertility challenges, age-related factors, and previous treatment outcomes. With personalized guidance, state-of-the-art laboratory support, and a patient-first approach, we ensure couples receive accurate information, transparent counseling, and care aligned with the highest standards of reproductive medicine. Our goal is to help you move forward with greater confidence on your path to parenthood.