Preimplantation Genetic Screening

Genetic screening for your embryos to improve your chance of IVF pregnancy.

Preimplantation Genetic Screening (PGS) is a form of IVF genetic testing that checks if your embryos have the right numbers of chromosomes for a successful ongoing pregnancy, at an early stage prior to embryo transfer.

Some embryos which may appear normal under the microscope may in fact be chromosomally abnormal – known as aneuploidy - and don’t have the required 46 chromosomes in each cell.

As the embryo’s genetic ‘instructions’ are incorrect, it can’t form a healthy baby, and in many cases affected embryos either do not implant or miscarry.

PGS may be discussed with you as part of your IVF cycle if you have:

  • Had recurrent pregnancy loss/miscarriage
  • A history of failed IVF despite the transfer of what appear to be good quality embryos
  • Are an older woman. Older women are at a higher risk of producing abnormal embryos due to age.

Benefits of Preimplantation Genetic Screening

Preimplantation Genetic Screening may:

  • Help you achieve pregnancy in the least number of IVF cycles.
  • Help you avoid future failed IVF cycles and pregnancies. If PGS shows you have only abnormal embryos, you can consider alternative ways to have a family such as the use of donor sperm and donor eggs.
  • Significantly reduce the risk of pregnancy with an abnormal embryo, which is likely to reduce your risk of miscarriage.
  • Detect the majority of affected embryos before IVF transfer, improving your chance of a healthy pregnancy.

Meet our first PGS baby

Joanne and Andrew had their baby, Ernest Thomas, with the help of PGS.

Baby Ernest was born in April 2018, after our fertility doctors identified that genetically-abnormal embryos together with a misplaced window of implantation were the cause of the couple’s fertility struggles.

Read their story

Preimplantation Genetic Screening process

IVF cycle

You will undergo ovarian stimulation to produce mature eggs, which are then fertilised in our laboratory. We will monitor embryo development.

Blastocyst culture

We will advise if any of your embryos reach the required Day 5 Blastocyst stage for PGS testing. We will check your embryos have high-quality cells and are suitable for biopsy.

Cell extraction

Several cells will be carefully taken from each embryo by our embryo biopsy practitioners and transferred to a special genetics laboratory for testing.

Embryo preservation

Whilst we await your PGS results, your embryos are cryopreserved. Results take around two weeks.

PGS results

Our embryologists will use the results to determine which of your embryos are suitable for transfer. By using PGS, it is very likely that you will have fewer embryos available for transfer than you would have had if you did not do PGS. This is because embryos that test grossly abnormal are not transferred.

Frozen Embryo Transfer

You will undergo a Frozen Embryo Transfer, which involves optimising and preparing your uterus for pregnancy and precisely timing your embryo transfer. Only one embryo will be thawed and transferred in each cycle to reduce your risk of multiple pregnancy.

Should I have PGS as part of my IVF cycle?

Deciding to proceed with PGS is a very sensitive and individual decision.

Your Manchester Fertility consultant will discuss the benefits and risks with you in your particular case, so you can make an informed choice about whether to have PGS in your IVF treatment.

Preimplantation Genetic Screening facts

PGS limitations

PGS identifies if an embryo has more or less whole chromosomes than the required number to develop into a healthy baby – so it may not detect abnormalities involving smaller pieces of chromosomes and other types of chromosome anomalies.

PGS, genetics and gender

PGS does not detect genetic disease mutations or test for specific genetic conditions. We cannot tell you the gender of an embryo.

PGS suitable embryos

PGS can only be performed on embryos that have reached Day 5 Blastocyst stage. This is because PGS tests the cells from the embryo that form the placenta. Only embryos that have reached Blastocyst stage will have these cells.

PGS safety

PGS is a very delicate and intricate procedure using state of the art technology, and Manchester Fertility embryologists have had intensive embryo biopsy training to perform PGS, with less than 1% risk of damage to an embryo during cell extraction.

PGS and frozen embryos

PGS can be performed on embryos already frozen in storage with us. We can thaw these to perform testing if advised. Your embryos will need to be re-frozen afterwards, which we can do successfully and at minimal risk to your embryos.

PGS risks

PGS may show you have no normal embryos which are suitable for transfer. And although PGS is highly accurate, the risk of a pregnancy affected by a chromosome abnormality is not removed entirely.

Learning Centre

Learn more about the testing we can carry out, fertility treatments and how we can help you have a baby in our Learning Centre. Read through our blog library, browse our FAQs, explore our patient guides or ask us a question via our free Ask the Expert tool.

Learning Centre


How long should we be trying for a baby before we get fertility help?

Some couples get pregnant quickly and easily, others can take a lot longer. There is no set point to seek fertility help, although generally many people turn to their GP if they have not conceived after a year of trying for a baby. 

What can be done to help improve a low or poor sperm count, or improve poor sperm quality?

There are no effective, simple measures to instantly improve sperm quality. However, adopting a healthy lifestyle is beneficial so men should not smoke or drink excessive amounts of alcohol. It’s a myth that wearing loose underwear can help improve sperm quality or count.

How do we find the best fertility clinic for us?

Firstly visit the Human Fertilisation and Embryology Authority’s website (HFEA) for a list of registered clinics local to you. Then ring up the fertility clinic and ask for brochures or information, or visit the clinic’s website. Don’t be afraid to go and tour the clinic. At Manchester Fertility you can book in for an informal, free 'one-to-one' appointment so that you can come and visit us, our friendly team will be on hand to answer any questions you might have.

When do I start to pay for fertility treatment? Do you offer free fertility consultations?

Fertility treatment costs start at the point of an initial consultation with one of our fertility consultants. As we are a private clinic we do not offer free fertility consultations. View our prices page for more information about our fees and charges. 

How much does IVF or fertility treatment cost?

IVF costs vary depending on which clinic you choose. You will need to pay for the initial consultation, any pre-treatment tests or scans, and then for the actual treatment itself and any necessary medications. For more details, see our prices page. 

Does my BMI and weight affect IVF treatment?

To undergo IVF treatment it's not about your weight but your BMI. If you're struggling to do find work out your BMI, try this handy online BMI calculator

Generally to receive IVF treatment on the NHS your BMI needs to be over 19 and under 30. To request IVF treatment with Manchester Fertility your BMI needs to be over 19 and under 35.

How can I get an appointment with Manchester Fertility?

You do not need a referral for an appointment with us. You can self-refer.

What IVF success has Manchester Fertility had?

Manchester Fertility has been at the forefront of IVF technologies since we opened over 30 years ago. Back then, IVF was a fairly new development, but it is now used the world over. We now welcome hundreds of new patients each year and have seen over 5,000 babies born thanks to the skill and expertise of our team.

We are continuously looking at new ways to overcome fertility issues, through dedicated research, to make sure our patients always benefit from the latest fertility treatments available. 

I already have a child but I am having problems getting pregnant again. Is there something wrong with me?

Secondary infertility – the inability to have a second or third child despite have a successful pregnancy before – is not uncommon. But you may be worrying over nothing. Remember, infertility isn’t defined until you have been having regular, unprotected intercourse for up to two years without falling pregnant, so it could just be that this time it’s taking longer than before to conceive. Your age could also be a factor, remember that fertility starts to decline from age 30 onwards and even more so from age 35. But if you think you need fertility help, don’t hesitate seeing your GP or contact us,

Can I get IVF treatment on the NHS?

Local clinical commissioning groups (CCGs) decide whether to fund IVF (in vitro fertilisation) treatment on the NHS. Guidance from National Institute for Health and Care Excellence (NICE) recommends that up to three IVF cycles should be available on the NHS if:

  • the woman is aged between 23 and 39 at the time of treatment, and
  • one or both of you has been diagnosed with a fertility problem (such as having no sperm or both fallopian tubes blocked), or
  • you have been infertile for more than three year

Women aged 40-42 who have not conceived after two years of regular, unprotected sex or after 12 cycles of artificial insemination should be offered one IVF cycle if the following criteria are met:

  • they have never previously had IVF treatment
  • there has no evidence fertility problems due to a low amount of eggs (low ovarian reserve)
  • there has been a discussion of the risks of IVF and pregnancy at this age

Implementation of this guidance by CCGs currently varies as it is only guidance and not mandatory and some CCGs apply additional criteria that affect access to NHS-funded IVF treatment. You can find out more on the NHS website

Do you offer fertility treatment via the NHS?

No, we do not offer fertility treatment on the NHS as we are a wholly private fertility clinic. However certain Clinical Commissioning Groups (CCGs) will consider allowing you to transfer the funding for your NHS IVF cycles to us. If you’re eligible for fertility treatment on the NHS, you may be able to Transferring your NHS funded IVF treatment unit but would firstly need to discuss this with your CCG.  More information can be found from Fertility Network UK.

What hours are you open?

Being flexible with our opening times is vital for our patients at Manchester Fertility. We always aim to see you at times convenient to you. Our current opening times are shown on our contact page. You will always see the most appropriate staff member for your needs.

What is the EmbryoGlue Treatment you offer?

EmbryoGlue is not a treatment we charge extra for – we use it as a supplement to the culture media used in the development of your embryo in our laboratory. We started using it because studies have shown it helps improve the chances of pregnancy by encouraging your embryo to implant successfully. It is a culture medium that mimics the natural molecules and fluids you’d find in your own body if you were going through pregnancy naturally.

Your embryo is placed into the EmbryoGlue just prior to transfer – and the properties it contains helps the embryo ‘stick’ to your uterus. Once an embryo transfer is carried out, we can never guarantee it will successfully implant for pregnancy – but 13 separate studies have concluded that the use of EmbryoGlue, thanks to its high levels of hyaluronan, increases both clinical pregnancy rates and live births. And so we now use EmbryoGlue for all embryo transfers at no extra cost to you. For more information about EmbryoGlue, you can visit this link.

I’m in a same-sex relationship and we would like to have a family. Can you help us?

Yes, we welcome many same-sex couples through our doors for pregnancy help, in fact we have a great reputation for it - whether you need surrogacy, a donor egg or donor insemination. For information about the fertility treatments we offer to help you, visit our donation section

Is there a waiting list for fertility treatment at Manchester Fertility?

No, there is no waiting list for fertility treatment with us. This includes IVF treatment, donor sperm, donor eggs, intracytoplasmic sperm injection (ICSI), ovulation induction and intrauterine insemination. We also have our own successful egg-sharing programme.

I want to get pregnant but I’m over 40 years of age, can you help me conceive?

Yes, we do infertility procedures for women up to the age of fifty. However, you need to consider the fact that live birth rates for older women in their mid-40s, who wish to use their own eggs to conceive, is generally extremely low. Your options will include ovarian stimulation, and intrauterine insemination or IVF. Dependent upon your individual case, you may need to consider using donor eggs to get pregnant. For more details, call us on 0161 300 2730. You can also read our Guide for Older Women.

"Thank you so much to everyone at Manchester Fertility who has helped us create our gorgeous family"

Sam and Vinnie, Jul 2018

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