HFEA.gov.uk uses cookies to deliver content and make improvements to the website.

Configure cookies
Skip to main content
Menu toggle
Home Contact us

Embryo research project summaries

On this page you will find summaries of embryo research projects taking place in the UK. 

Biochemistry of early human embryos

Hull IVF Unit

We know very little about the processes that form a human embryo and why some embryos turn out to be healthier than others. The purpose of this work is to carry out a detailed examination of the development of the early human embryo, particularly how it generates the energy it needs to grow. This knowledge will help optimise embryo culture and transfer procedures to enhance IVF success rates.

A second area of increasing importance is how the environment in which early development occurs can influence the long-term health of the babies born. For example, a woman’s body weight affects the quality of her eggs and embryos; a detailed understanding of which could increase the chances of a healthy pregnancy and a healthy baby.

The aims of this research are:

  1. To devise a simple, reliable method for embryo selection;
  2. to discover whether the preconception environment, including maternal body weight can affect the health of eggs and early embryos.

This information will enable couples trying for a baby naturally or through IVF to be provided with sound preconception advice. The research uses highly sensitive laboratory tests, most of which are non-invasive, to study the biochemistry of individual human embryos, donated to research after treatment.

The data can then be related to the ability of the embryos to develop successfully in culture. Pilot work will be carried out in the laboratory on animal embryos to confirm the approaches are feasible before conducting this essential research on spare human embryos.

The data will provide reassurance that a non-invasive test to select single embryos for transfer is safe and effective such that clinical trials could safely be undertaken and to demonstrate the importance of the pre-conception environment in ensuring the health of embryos conceived via IVF, and the short and long-term health of the babies.

Human egg and sperm interaction and signalling - Centre for Human Reproductive Science

University of Birmingham

During fertilisation, the sperm penetrates the surrounding of the egg and fuses with the egg which leads to an embryo forming. If fertilisation fails an embryo does not form. This project examines both scenarios in detail. The results of the project could show how sperm and eggs may talk to each other and enable understanding of how these things go wrong and may cause infertility, but also to devise better future fertility treatments, alongside an understanding of their safety.

In this project imaging (microscopy) techniques will be used to examine in detail the events occurring as human sperm and eggs interact. Genetic technologies will also be used to assess whether any embryos formed are ‘normal’ or would have potential problems that may, for instance, cause miscarriage. This type of research may also generate new contraceptives.

Towards improving assisted reproductive technologies for the treatment of infertility and prevention of disease’

Newcastle Fertility Centre at Life in collaboration with the Francis Crick Institute

The focus of this project is to find ways to prevent transmission of mitochondrial DNA disease to improve outcomes of assisted reproductive technology for the treatment of infertility.

The three main aims of this research are:

  1. Develop new clinical treatments to minimise transmission of mitochondrial DNA mutations (change in genes) from a mother to her child,
  2. Improve the outcome of infertility treatments by studying cellular and molecular events that occur before the embryo is implanted and
  3. Investigate how chromosomal abnormalities in eggs and embryos arise, to understand what makes eggs of older women more likely to have chromosomal abnormalities.

Developing criteria for estimating quality of stem cells derived from human embryos

Guys Hospital, London

Stem cells are unique cell populations that can copy themselves exactly and turn into new cell types (such as muscle or brain cells). Stem cells can be obtained at the early stages of embryo development; these cells are called human embryonic stem cells (hESC).

They also could be used in research to develop drugs to treat serious diseases, or to repair organs following a stroke or heart attack. Although there is a lot of hype around stem cells their potential is not fully realised yet. The project involves measuring and observing the way stem cells copy each other so that researchers can define norms and standardise protocols that would assure quality and assurance in the use of stem cells. The hESCs are programmed to turn into a specific cell type, so the researchers will try to figure out how to know what kind of cell a hESC will turn into.

Indicators of egg and embryo development

Centre for Reproductive Medicine Coventry, University of Warwick, University of Edinburgh

Many eggs and embryos have anomalies that render them incapable of developing, or less likely to produce a pregnancy, but some embryos can overcome problems and get back on the right track.  Embryologists do not yet know in enough detail exactly what problems arise, how eggs and embryos respond to problems, or how embryos grow and implant into the uterus.  Consequently, clinical grading of embryos and estimates of pregnancy chances have poor predictive value. 

This work focuses on the following:

  1. The reasons why egg quality declines as women get older.
    This will involve studying immature and mature eggs from women of different ages to look at the molecular machines that hold chromosomes (genetic material) together. This is particularly critical in the egg just before and during fertilisation as well as when the first cells of the early embryo form.  It has been found that the structure of the molecular machines is looser in older women, which may allow chromosomes to move in ways that can cause abnormalities in the embryo.  Using techniques developed in other cell types, live cell imaging will be used in eggs to observe these machines and chromosome movements directly.  This will help to explain the causes of the high rates of abnormality and miscarriage in pregnancies in older women.   
  2. Communication between the embryo and the endometrium (lining of the uterus) at implantation.
    This will involve studying signals that embryos produce and their influence upon endometrial cells with a view to understanding and diagnosing embryo quality based upon the profile of signals and responses. It is hoped that this may lead to new methods to increase the chances of implantation.

Genetic Profiling for Infertility and Development of Novel Preimplantation Diagnosis

Human Genetics & Embryology Laboratories, University College London

Early human development is complex and involves the gradual ‘switching on’ of the DNA from the embryo (embryonic genome activation). We have been studying genetic abnormalities that can arise in early human embryos. This work has shown that many embryos generated in the laboratory by in vitro fertilization (IVF) have at least some cells with chromosomal abnormalities.

We suspect that this is the main reason why so many IVF embryos die. Our current research aims to study the genetics of early development and infertility and to examine methods that might improve IVF outcome. We intend to do this study through the analysis of blood, cumulus/granulosa cells (cells surrounding the ovary), eggs, sperm and embryos by examining a variety of genetic markers. We will compare the genetic profile of embryos that develop well with those embryos that do not progress beyond a few cells.

Investigation of causes and molecular mechanisms of abnormal one-pronucleus zygotes after Assisted Reproductive Technology treatment

MRC Centre for Reproductive Health

During normal fertilisation (both natural and in IVF/ICSI cycles), the sperm and egg genetic material (the chromosomes) can be seen in two separate structures called ‘pronuclei’, just before they fuse to form the genetic material of the new embryo. Seeing 2 pronuclei is a sign of normal fertilisation, and embryologists look for this as part of their assessment. Sometime however only 1 pronucleus is seen, in about 3 to 20% of fertilised eggs, and this cannot form a normal embryo. The causes of this are unknown. In this study, we would like to investigate what has happened in these abnormal embryos. The knowledge we gain from this study may help us to identify some causes of abnormal fertilisation and perhaps in the future design and develop a potential treatment strategy.

Mechanisms of stem cell development during human embryogenesis

MRC Laboratory of Molecular Biology

Six days after fertilization the human embryo contains two main types of stem cells, those that will generate the foetus, and those that will form the placenta. As soon as the embryo implants in the womb, these stem cells start to divide and reorganize, initiating a process of specialization to generate cells with many different identities and functions. All these events need to be coordinated or the pregnancy will fail. Approximately 30% of human embryos fail to develop beyond implantation but the reasons why remain unknown. To understand the causes of failure we will follow three complementary approaches. We will culture human embryos using a system that permits development up to day 13, and analyse their development using biochemical techniques. We will derive stem cell lines from the embryos to characterize their properties. We will alter the cellular composition of the human embryos by introducing human stem cells, which can be genetically modified to investigate the function of specific genes and proteins. Our studies will be important to understand the reasons behind early pregnancy loss and to devise potential strategies to overcome this medical problem.

Human gamete interaction and signalling

Centre for Human Reproductive Science, The University of Birmingham

The Centre for Human Reproductive Science develops research and innovation in fertility diagnosis and treatment, working in partnership with the Birmingham Women’s Fertility Centre at Birmingham Women’s Hospital and the University of Birmingham Medical School.

ChRS integrates infertility expertise from multi-disciplinary research collaborations worldwide. Recent progress has included results from the HABSelect Trial where we demonstrated how simply changing the method for sperm selection can radically reduce the chance of a miscarriage in older females seeking treatment – something that to date had always been considered a female-factor.

We are developing the next stage of male treatment and diagnosis by creating tools to assess the rapidly beating sperm flagellum and how the tail can unlock insight that has been previously unattainable.

Our current aims are to understand how we can link sperm quality to chance of future children. This includes looking to quantify the chance that individual sperm with set characteristics have to fertilise an egg. It also makes us interested in eggs that fail to fertilise, and understanding whether sperm were in them, as well as the way that an egg selects a sperm, which includes the hormones made by the individual cumulus cells surrounding the egg and whether these differ in individuals, such as those with PCOS.

A big part of what we do aims to ensure the health of not just our children, but understanding the impact on their children too – enabling and protecting our future generations.

In vitro development and implantation of normal human preimplantation embryos and comparison with uni- or polypronucleate pre-embryos

University of Manchester and St Mary’s Hospital 

This project involves studying early human embryo development. The researchers want to find out what factors contribute to normal embryo development, and what happens when development goes wrong. They will be assessing the impact of sperm DNA damage and factors which might affect embryo development and implantation into the womb, including the culture environment and the effect of freezing embryos.

It is necessary to use human embryos for this research as although important information has come from studies of animal embryos, they develop differently to human embryos. 

Derivation of pluripotent human embryo cell lines

MRC Human Genetics Unit, Edinburgh

Embryonic stem (ES) cells were first identified in mouse embryos in 1981. Cells similar to ES cells can be made by manipulating differentiated cells (for example skin or nerve cells) to make ‘induced pluripotent cells’ (iPS) cells.

ES and iPS cells have the unique ability to turn into any tissue in the body. ES and iPS cells can now also be obtained from human embryos and adult tissues. However, human stem cells are not as consistent and reliable as mouse stem cells. In this project, human and mouse embryos are compared with the aim of developing ways to improve human ES cells so that they’re easier to grow and can differentiate into wider range of tissues.

By using specially optimised culture conditions for human ES cells, they can be instructed to form structures resembling blastocysts, called ‘blastoids’, comprising trophectoderm, epiblast and hypoblast. Blastoids can be generated in large numbers, enabling us to test effects of appropriate chemicals, or genetic variation on their development over the next few days.

Derivation of stem cells from human embryos: the development of human embryonic stem cell cultures, characterisation of factors necessary for maintaining pluripotency and specific differentiation towards transplantable tissues

The Francis Crick Institute

This research is concerned with early human embryo development. It is hoped that the results of these studies will benefit medical knowledge in a number of important ways.

Firstly, by improving understanding of the conditions that are important for growing human preimplantation embryos in a petri dish. These insights can hopefully lead to improvements in the treatment of infertility.

Secondly, by improving our understanding of how early human embryo cells become more specialised during early development. The first critical step in this process is when a small subset of cells are set aside to eventually form the foetus, whilst another subset of early cells differ in their fate to become the placenta (which supports the development of the foetus throughout the pregnancy). The researchers will be trying to find out how these specialisation events occur and are regulated before implantation. Understanding the genes that are essential for this first important specialisation process could provide insight into some causes of pregnancy failures and birth defects. Understanding this important switch in cell fate may also provide a deeper understanding of stem cell formation.

Lastly by developing stem cell lines that can be taken out of the embryo and multiplied in the laboratory for many years. This can help to study and better understand devastating human diseases at the cellular level in the laboratory and potentially develop new drug treatments.

Filming of human implantation in vitro

Physiology Laboratory, University of Cambridge

A high proportion of natural abortions occur because of developmental failure as the embryo implants into womb. To avoid such failures in the IVF clinic, it would be helpful to know what an embryo must achieve during the initial days when it is placed in the mother’s womb. This project involves culturing embryos in an in vitro (artificial) environment that has been shown to permit the correct development of an embryo until day 13.

For the first-time this allows researchers to study human embryo development from day 7 to day 13, a period that normally cannot be seen. This research will help in understanding the causes underlying early pregnancy loss.

Investigation into the role of sperm PLCzeta in human egg activation

Cardiff University School of Biosciences

At fertilisation, the sperm fuses with the egg and sends a calcium signal to trigger it to begin development. Without this signal, the process of fertilisation is not successful and an embryo cannot be made. In a proportion of IVF and ICSI treatments it appears that the egg fails to fertilise because of a lack of this activating calcium signal.

Previous research in mouse eggs has shown that sperm contain a protein, referred to as PLCzeta, which enters the egg during fusion and triggers the calcium changes that lead to egg activation and embryo development. This project aims to extend some of these studies to human eggs.

In this project, human eggs that have failed to fertilise during IVF treatment cycles will be injected with the PLCzeta protein to see how effective it is in stimulating the calcium changes that cause egg activation. The effectiveness of PLCzeta protein will be compared with certain chemicals that have been used by some clinics to stimulate calcium changes in human eggs that have failed to activate after ICSI treatment.

This work could provide important information on how the sperm normally triggers development during human fertilisation. It may help explain why some eggs fail to fertilise after procedures such as ICSI, and it would offer new ways to overcome such fertilisation failure.

Improving methods for preimplantation genetic diagnosis of inherited genetic disease and predicting embryo quality

Guys Hospital, London

This project is testing a technique involving the splitting of embryos. If successful, it could be possible to split one embryo into two, both of which will have the same genetic information. Embryos for research can be hard to obtain so by being able to split one, it reduces the number of embryos used and avoids genetic background bias.

Artificial egg activation and egg/embryo movements as early indicators of embryo quality

Oxford Fertility

At fertilisation, the sperm activates the egg to begin development in a process called egg activation. A protein called PLCzeta is important in this process. If there is not adequate PLCzeta then the egg may not be successfully fertilised. Men without adequate PLCzeta may therefore be infertile. This project involves using a synthetic version of PLCzeta created in a lab and seeing if it can be used for fertilsation where there are low levels of natural PLCzeta.

The second part of this project involves using high-frequency time lapse filing to observe the tiny movements that take place in an egg during the first few hours after activation. These, and other experiments on eggs and very early stage embryos, will increase our knowledge of the processes that occur around fertilisation. In the future, the synthetic PLCzeta could be used to help in cases where there are egg activation problems, and use the time lapse technique to predict which embryos are healthier for transfer in IVF.

Comparative studies on human embryonic growth and male germ cells

Institute of Reproductive and Developmental Biology Centre, Imperial College London

This project involves studying early human embryo development. From this work researchers aim to develop biomarkers that provide an indication of embryo potential. Embryo selection methods are currently based on detailed morphological parameters (structure and shape of the embryo) associated with successful IVF.

Although this morphological assessment remains the easiest way to predict embryo viability, even high-quality morphological appearances often can’t accurately predict a successful implantation. Metabolic assessment (measurement of chemical processes) of embryos may provide greater understanding and be representative of the embryo viability. This can also be done through analysis of the products left over in the culture media that the embryo is incubated in during the first few days of growth.

Laboratory methods to complete this type of assessment have been developed to become more sensitive and accurate. It is hoped these approaches will benefit understanding of early human embryo development and metabolism, and this can then lead to improved methods of embryo selection. 

Environmental sensitivity of the human preimplantation embryo

Centre for human development, stem cells and regeneration

There is growing evidence that the environment experienced by early embryos, for example, the way they are grown in the laboratory, or the conditions they experience in the mother’s body, can influence growth and development, both in the womb and after birth.

Such environmental conditions can make long-lasting changes to the way the embryo’s genes work. The purpose of this project is to investigate when and where a gene or its protein product are active using sensitive molecular and microscopic procedures designed for early embryos; also how this pattern influences the embryo’s growth, development and physiological functions. The parents’ body condition, for example age or BMI, will be examined to see how this affects the way the embryo grows and activates its genes, including those known to be important for making human embryonic stem cells, and whether this is influenced by the way the embryos are grown in the laboratory.

This research aims to improve our understanding of the mechanisms that regulate the embryo’s ability to develop under different conditions to maximise developmental potential whilst minimising possible risks for long-term health complications. This will have a significant impact on the treatment of infertility and inform advice given to patients.

A research study to investigate factors supporting in vitro human embryo development

The Babraham Institute

Our project aims to investigate the molecular factors underlying human embryo development during the transition from pre-implantation to early post-implantation. This period is characterised by major genetic and epigenetic changes that occur during the specification of embryonic and extraembryonic cell lineages and subsequent implantation of the embryo into the uterus. Furthermore, because epigenetic marks formed during this period are inherited by all subsequent foetal and adult cells, errors that arise during this early stage of development might promote the onset of certain disorders later in life, and this process is therefore important to understand in greater detail. To address these questions, we aim to optimise in vitro culture conditions to promote the accurate development of human embryos until day 14, and using this improved system we will examine changes in gene activity and epigenetic patterns in embryos from pre- to post-implantation. We will determine whether specific patterns are established differently between embryonic and extraembryonic lineages, and also in response to the interactions formed between the embryo and endometrium. Our research will identify important new insights into the processes required for healthy embryo development, which we anticipate will help to improve IVF outcomes and potentially identify causes of infertility in patients.

Review date: 24 September 2026