ICSI (Intracytoplasmic Sperm Injection)

This micromanipulation method allows a single sperm to be injected directly into an egg in cases where the sperm quality is not suitable for standard IVF. According to the best information available to date ICSI is not harmful to the embryo and does not increase the risk of birth defects.


The PICSI device helps embryologists in sperm selection. It is based on research documenting that mature and structurally sound sperm will bind to hyaluronan, and is a reliable alternative to more expensive DNA integrity assays.
The PICSI dish contains samples of hyaluronan hydrogel. The visual selection alone cannot identify the best sperm, so selecting a bound sperm ensures that the sperm selected is the optimal sperm from the sample for fertilisation.

AH (Assisted Hatching)

This technique, usually performed shortly before embryo transfer, helps the embryo to hatch from its outer shell and can improve the chances of embryo implantation and pregnancy.

Cultivation to the blastocyst stage

A blastocyst is the embryo stage seen typically on day 5 after fertilization, which has developed 2 cell types and a central cavity filled with fluid. The surface cells around the cavity (trophectoderm, TE) will later
become the placenta and the centrally located group of cells (inner cell mass, ICM) will later become the baby. Culture to this stage allows the embryologist to choose the best quality embryo(s) for transfer which can improve the chances of pregnancy and help to minimize the risk of multiple pregnancy (by transferring a single blastocyst). Not all embryos will reach the blastocyst stage and it may only be recommended when enough eggs have been retrieved. Blastocysts are suitable for genetic testing and can be successfully cryopreserved.
Another argument favoring extended cultivation is that in a natural pregnancy, a 3 day old embryo resides in the tubes and only reaches the uterus approximately on day 5 or 6. Although only one third of embryos will reach this stage, the ability to generate blastocysts is a good predictor for pregnancy. For the same reason, however, extended cultivation is attempted only when enough eggs have been retrieved. Due to the higher likelihood of survival, fewer eggs are transferred back to the uterus, minimizing also the risk of a multiple pregnancy. Blastocysts are suitable for genetic testing and can be successfully cryopreserved.


Cryopreservation or freezing is possible for eggs, embryos and sperm.
We use vitrification to freeze embryos rather than the conventional slow freezing process since the rapid cooling (around 7000 times faster than slow freezing) appears to be less damaging to embryos.


The latest technology for continuous assessment and culture of embryos – available for £400 now at City Fertility.
Until recently, embryo monitoring has involved the removal of in-culture embryos from an incubator for microscopic assessment at a specific moment in time.
GENNET City Fertility offers time-lapse imaging of embryos utilising the EmbryoScope TM incubator system – with a microscope and camera system integrated within the incubator your embryos are monitored 24 hours a day whilst they are in culture allowing embryo development to be assessed and observed as a time-lapse movie.
In addition, there is reduced disturbance to your embryos than using traditional incubation methods as the embryos remain in a stable environment throughout the culture process.
EmbryoScope ™ provides our team of embryologists with additional morphological and developmental information about your embryos, including assessment of morphology, multinucleation, cell division patterns and timings – all contributing to selecting the better quality embryo(s) to transfer.
Key Benefits of time-lapse imaging
Selection of “highest potential” embryos for embryo transfer giving you your optimal chance of having a baby
More stable environment for your embryos during culture
Time-lapse developmental video of your embryos for you to keep
To find out more about time-lapse imaging at GENNET City Fertility, why not come and see us for an informal visit?
020 8209 3226


The intracytoplasmic injection of sperms (ICSI) is a micromanipulation technique, which consists of the incorporation of a sperm into the ovum by means of a micro-needle. This technique represents a distinct progress in the treatment of male infertility. Because ICSI requires only one sperm for each ovum, it is a solution for situations with a low number of sperms and defects of mobility.
Even the azoosperms from imperforation of outlet passages can be treated, because the sperms can be obtained directly from the didymis with a method MESA/TESE. Due to the high success rate of fertilization which is achieved by this method (approximately 7 out of 10 eggs are fertilized) it became a standard IVF procedure in practice.


During IMSI (intracytoplasmic morphology selected sperm injection under 6000x zoom), similar like during ICSI, one sperm is chosen and inserted with a sharp capillary directly into the egg. The difference between IMSI and ICSI is that for sperm choosing an enlargement of up to 5times larger is used, which allows more detailed evaluation of its morphology.
IMSI is mainly used in cases of repeated unsuccessful IVF treatments, repeated abortions without obvious reasons, or low (25%) or no fertilization of oocytes after ICSI. There is the possibility of its use also in cases of serious teratozoospermia determined by a conventional evaluation.


PICSI is a method of sperm selection intended for ICSI. It imitates the natural linkage of mature sperms on cumulus oophorus of the oocyte in the in vitro fertilization process.
The main part of cumulus oophorus (cell layer surrounding the oocyte) is hyaluronan, which is a protein on which mature sperms are linked through hyaluronan-specific receptors. Those receptors are only on the head of a mature sperm. Immature sperms do not have receptors and therefore can not be linked. Thereby, sperms with a normal frequency of chromosomal aneuploids and sperms without fragmented DNA bind themselves on the oocyte in a natural process of fertilization. Therefore, the sperm with the best genetic information is naturally selected.

In the selection process of PICSI, hyaluronan is contained in the gel on the bottom of Petri dish. To this gel a medium with sperms is added.


migrate to the gel and mature sperms are linked through receptors on the hyaluronan in the gel. This is shown by their being “stuck” by the head to the bottom of the dish, but the energetic movement of the flagellum does not stop (movement in place). Immature sperms penetrate through the gel and embody a continuously progressive movement. Linked sperms with intensive movement of the flagellum are then chosen and used in the classic process of ICSI.
PICSI indication:
Hard oligozoospermia and/ or teratozoospermia (≥95% of pathological sperms)
Low percentage of fertilized oocytes (30%) or not fertilized oocytes after ICSI
Repeated abortions and/ or repeated ET without implantation

Extended cultivation

An embryo is usually in the developmental stage of blastocyst on the fifth day after the fertilization. This means that there are already two types of cells that developed and that the inner cavity is filled with liquid. The first type of cells on the surface of the cavity (trophoectoderm) later becomes placenta and from the cells which are stored inside (embryoblast) the fetus develops. Extended cultivation and transfer on day five or six imitate the course of a natural pregnancy, when the first days after fertilization the embryo moves in the fallopian tube and reaches the uterus also only on day five or six. Only a third of the embryos reach the blastocyst stage and therefore, extended cultivation
can be considered a method of selecting embryos of the highest quality. For the same reason, extended cultivation is performed only when there is a sufficient number of embryos. Due to the higher probability of survival it is possible to transfer one embryo after extended cultivation (SET), which decreases the risk of a multiple pregnancy. Surface cells of the blastocyst (trophoectoderm), which are extracted on day five, are suitable for genetic testing. Blastocysts can be frozen using vitrification and they can be stored with a good perspective of development after defreezing in subsequent cycles.


It is a culture medium which represents a new assistance for patients who have suffered miscarriages. The medium contains the growth factor cytokine (a signaling protein that essentially participates in the immunological response of the organism), which has a verifiably positive influence on a group of patients with recurrent spontaneous abortions.
A spontaneous abortion in itself is caused by an imbalance between the endocrine system and the immune system and a deficient development of the embryo, placenta and uterus. As a consequence, this leads to an erroneous communication between the embryo and the uterus, to a wrong direction of the implantation and, eventually, to a rejection (expulsion) of the implanted embryo.
Cytokines are important regulators of communication between the embryo and the uterus. The cytokine (GM-CSF), which is included in the EmbryoGen medium, verifiably improves the development of the embryo and the placenta and it is not a threat to the cultivation of human embryos. This broad-acting cytokine creates an environment for the in vitro cultivated embryos that rather resembles the in vivo environment (under natural conditions) and thus increases the ability of the embryos to implant (sink into the endometrium) and remain implanted (survive and continue to grow in the endometrium).
The medium is used for the cultivation of fertilized oocytes and embryos up to the age of 3 days.


What is EmbryoGlue?
EmbryoGlue was designed in such a way that its composition imitates the uterine environment at the time of the implantation. It is not glue in the true sense of the word, but its function is similar to the function of glue, because it increases the chance of implantation of the embryo in the uterus. EmbryoGlue is enriched with saccharides and amino acids that support the embryo during the transfer and implantation. It also contains a relatively high concentration of hyaluronan and recombinant albumin, the safest possible source of proteins.

What is hyaluronan?
Hyaluronan is a natural substance which is commonly present in all tissues of human body. Its concentration in the uterus at the time of the implantation increases. Uterine wall and embryo contain receptors for its molecule. It is believed that hyaluronan EmbryoGlue establishes a connection between the embryo and the uterus.
It “glues” the two together, so to say. Hyaluronan in a high concentration also thickens the solution and thus makes it due to its consistency similar to the liquid that is usually found in the uterus. This enables a better blending of the medium and the uterine liquid, which should minimize undesirable movement of the embryo.

What is recombinant albumin?
Recombinant albumin is another important part of EmbryoGlue. In contrast to the most commonly used sources of albumin it has its origin neither in any animal or human products. It is therefore much safer both for the mother and the future baby, because it eliminates the risk of cross-contamination.

Who should use EmbryoGlue?
EmbryoGlue® brings along benefits for all patients who undergo embryo transfer in the course of assisted reproduction. An independent research institute named “Cochrane Collaboration” evaluated all publications that deal with the influence of increased level of hyaluronan on the level of implantation during embryo transfer. They reached the conclusion that the results are better than those for transfers without hyaluronan. EmbryoGlue® is the only available product that is enriched with hyaluronan.
Further studies show that the number of children born in couples with a wide range of fertility disorders has risen significantly. EmbryoGlue® has proven to be an advantage, especially for patients that are older than 35 years, for patients who have experienced a failure of implantation earlier and for patients with unexplained cause of infertility. If you have more questions to EmbryoGlue® or if you want to know whether EmbryoGlue® is suitable for you, consult your physician.

Closer to nature
Nowadays scientists already understand physiological needs of gametes and embryos better. Thanks to the development of the media that imitate the changes of female reproductive tract we are capable of optimizing the development and quality of embryos.
EmbryoGlue® is an important part of the media series G-Series™. We drew our inspiration from the embryo and the mother in the course of its development.
More children born with EmbryoGlue
Customarily used medium

Pregnancies that were terminated with birth
This is a retrospective research study from the years 2004-2008 which compares EmbryoGlue with a customarily used transfer medium. The data were collected from approximately 1300 patients.


Assisted hatching
The assisted hatching is a micromanipulation technique performed usually on the 3-6 day-old embryo, closely before its introduction into the uterus. The erosion of the zona pellucida of the embryo makes its migration and later.
nesting easier. The AH can be performed mechanically (with a glass micromanipulation awl), chemically (acid Thyrode solution), with a laser or using an enzymatic method.

Capturing and analyzing of the dynamics of embryonic development presents a new method of quality assessment of human embryos and it is a promising outlook for the future.
Our IVF laboratories are equipped with the cutting edge technology providing by Embryoscope – Embryo Monitoring System.
Embryoscope is a highly sophisticated instrument containing an incubator, microscope and computer. 40 Embryoscopes are currently installed in 11 countries. The IVF centers at GENNET are the first centers in the Czech Republic equipped with this instrument.
Using Embryoscope allows embryologists to monitor and evaluate embryo development without disrupting their natural environment. Dynamic scans and analyses of embryo development present a new method for observing human embryos and is a positive promise for the future.
Principal advantages of Embryoscope
Less manipulation of embryos reduces risk of harm
Instant and continuous monitoring of all embryos
Accurate regulation of CO2 and unique temperature control
Complete and accurate documentation of all embryos


Cryopreservation is a procedure which enables to store sperm cells or embryos in a frozen state at temperatures reaching up to -196 °C for later usage. If there are embryos available which have not been transfered in a stimulated cycle, they can be used after the cryopreservation in subsequent treatment cycles. Abnormal embryos are not frozen. In spite of the standardization of the procedures not all embryos survive the process of freezing and defreezing in such a state so that they can be transfered after
thawing. This method also enables preservation of sperm, for example before chemotherapy or when the partner cannot give a fresh sperm sample on the day of OPU.
Cryopreservation is performed at the request of the infertile couple and it is necessary to inquire in the IVF laboratory if its implementation was successful.

Vitrification is a method for long-term preservation of oocytes through the rapid cooling of cells. The principle of vitrification is the use of highly concentrated solutions of cryoprotective agents (substances protecting cells from damage from frost) in the freezing medium and subsequent abrupt hypercooling of cells (≥1000°C/min) at below -150 °Centigrade.Thanks to vitrification, women may have their eggs frozen for later fertilization.

Why it is good to have one’s eggs frozen?
During a woman’s lifetime, approximately 1-2 million eggs develop in her ovaries, but many of them disappear before puberty.¬ A woman of childbearing age has from 200,000 to 400,000 eggs, and approximately 400 of them will mature. With increasing age, the quality of eggs also decreases, and female infertility after reaching the age of 38 years is common.
Hence, if a woman of childbearing potential is not planning to have a child at the moment, vitrification of eggs may provide a better chance of getting pregnant later in life.
We recommend vitrification in the following cases
Before initiation of cancer treatment: chemotherapy may result in irreversible damage to the eggs
Other health-related reasons: e.g., when ovaries must be removed
Women of childbearing age who delay having children
Differences between vitrification and cryopreservation
During conventional cryopreservation, lower concentrations of cryoprotective solutions are used, and the cells are frozen very slowly (± 0,3°C/min). Although no water crystals are produced inside the cells during this procedure, such crystals are produced in the freezing medium, which can lead to their damage. During vitrification, formation of water crystals is avoided and the success of cell thawing ranges around 95%.