IVF and ICSI
What is IVF (In Vitro Fertilisation)?
In Vitro Fertilisation (IVF) is a process of getting pregnant where an egg is fertilised by sperm outside of the body, in vitro (which literally means “in glass”).
In simple terms:
- An egg is removed from the woman’s ovaries just before ovulation.
- The eggs are fertilised with sperm outside of the body in a laboratory. Fertilised eggs are called an embryos.
- 2-5 days later, if fertilisation and normal embryo development has occurred, the best embryo(s) are then transferred to the woman’s womb to grow and develop into a successful pregnancy.
You can find out more about IVF & ICSI below.
What is ICSI (Intra-Cytoplasmic Sperm Injection)?
ICSI (Intra-Cytoplasmic Sperm Injection) is a method of inseminating an egg by injecting a single sperm directly into the egg using a fine needle.
It is recommended in cases where there are not enough motile sperm to fertilize an egg using normal IVF. It is particularly useful in cases where sperm parameters are severely reduced. The procedure was developed in 1992 and has been a major advance in the treatment of male factor infertility.
While most studies on children born as a result of ICSI are reassuring, some concerns have been raised in recent years that these children may be at a slight increased risk of rare genetic abnormalities, called imprinting problems. These are, however, extremely rare.
How does ICSI differ from standard IVF?
ICSI is a method of inseminating an egg by injecting a single sperm directly into the egg using a fine needle. This differs from standard IVF where the sperm has to penetrate the egg by itself.
When is IVF and/or ICSI needed?
The original indication for IVF was damaged fallopian tubes, but it is now also used for a wide range of disorders such as unexplained infertility, endometriosis and male factor infertility.
The process is undertaken by couples who are having difficulty in conceiving, same-sex couples or single women wishing to have a baby through sperm donation.
How many visits are required for a cycle of IVF and/or ICSI?
The number of visits and cycles will vary from individual to individual, but usually it takes 2-5 monitoring visits and 8-12 days of stimulation.
A number of egg follicles need to develop in order to have a reasonable chance. Generally over half of eggs collected will fertilise and half of these will grow on as embryos.
Treatment is monitored through a combination of ultrasound and blood tests.
The stages of IVF and ICSI
1. Ovarian Stimulation
The chances of pregnancy with IVF are increased if more than one egg is recovered.
Therefore a crucial step in the treatment is the stimulation of the ovaries with fertility drugs with the intention of producing a number of follicles within which eggs will hopefully develop. The intention is to develop a minimum of 3 mature eggs. This process is called super-ovulation.
A number of different fertility drugs and protocols are used in the treatment to control the timing of egg release.
The most commonly used protocol for IVF is called the Antagonist Protocol. This involves stimulating the ovaries with FSH injections. An additional injection is introduced on day 5 or 6 of stimulation, with the aim to control the woman’s hormones. Regular transvaginal ultrasound scans will monitor the follicular growth. An injection will then be advised to mature the eggs and an egg collection will be planned.
In the event of suspected overstimulation, other drugs may be prescribed to prevent ovarian hyperstimulation syndrome.
The second protocol used for IVF is called the down-regulation or long protocol. A drug called a GnRH agonist (‘Gonadotropin Releasing Hormone agonist’) is given either by daily injection or as a nasal spray, with the aim of temporarily suppressing the woman’s natural hormones and controlling the timing of ovulation.
Down regulation is usually achieved after approx. two weeks. Once achieved, the GnRH agonist is continued in addition to injections of FSH ± LH that are given to stimulate the ovaries.
2. Ultrasound Monitoring
Initially the eggs are microscopic in size, but they grow into follicles (fluid filled sacs) which can be seen clearly on ultrasound scans.
We routinely monitor the development of the follicles using vaginal ultrasound scans. The follicles will almost be mature after 7-12 days of the injections (sometimes longer), at which point the woman stops her stimulation drugs and we give a carefully-timed trigger injection called hCG (human chorionic gonadotropin). This injection is usually given at night with the egg collection being performed 36 hours later in the morning.
3. Egg and Sperm Collection
This is a minor surgical procedure carried out using ultrasound guidance. Pain relief is provided intravenously during the procedure.
Egg collection is performed 36 hours after the hCG trigger injection.
A ultrasound probe is inserted into the with a fine hollow needle attached to it is inserted into the vagina to drain the fluid from each follicle.
The retrieved fluid is brought to the laboratory where it is checked for eggs. Although there are no guarantees, an egg is generally retrieved from most mature follicles. The eggs are identified and prepared for insemination or injection with sperm. The whole procedure takes about 20-30 minutes.
If the male partner’s sperm is being used, he will provide a semen sample either before or during the egg collection procedure. The sample will be then be specially prepared and used to inseminate the eggs.
Alternatively, if frozen sperm is to be used, this will be thawed out.
4. Insemination and Fertilisation
The afternoon following the egg collection (‘day 0’), the eggs are inseminated and left overnight to fertilise. Fertilisation usually happens in approx. 60-70% of the eggs collected. However this can range from 0% to 100% and 2-3% of couples will regrettably not achieve fertilisation of any eggs.
Only mature eggs can be injected and subsequently fertilise, so they are first checked to make sure they are mature.
There are 2 ways to inseminate eggs:
ICSI (Intra-Cytoplasmic Sperm Injection): When there are not enough motile sperm to fertilise the eggs using the standard IVF method, ICSI is used. After the eggs are checked, an embryologist selects an individual sperm and injects it directly into each egg.
Eggs are checked the following morning (‘day 1’) for fertilisation and patients are updated.
5. Development of Embryos & Blast Culture
Following the fertilisation stage, eggs progress on to the embryo stage. This is where the egg splits into 2 cells, then 3, 4 etc. Embryos are cultured or grown in the lab for a number of days, where they are monitored regularly by the embryologists.
Traditional standard incubators are an excellent environment for embryos to grow in. Alternatively an embryoscope is a highly specialised incubator with a built-in time lapse camera which can be used to help select the best embryo for transfer. Find out more about Embryoscopes.
The aim of embryo culture is to learn about the embryos to determine which are best to implant in the womb for the best chance of pregnancy.
Blastocyst culture refers to culturing or ‘growing’ embryo from the Day 3 stage to Day 5/6. A blastocyst is the next stage in development of an embryo and embryos should have reached this stage by Day 5. Growing embryos for a longer period in the laboratory provides additional information which can help in their selection for Embryo Transfer. While not every embryo will reach the blastocyst stage, those that do have a greater chance of implanting.
The best embryo(s) are transferred back to the womb in a procedure called Embryo Transfer, which can happen on Day 2, Day 3 or Day 5, depending on the number and quality of embryos in that given cycle.
6. Embryo Transfer
The embryo transfer procedure is quite simple and is usually pain free without the need for anaesthetic. One or two embryos suspended in a drop of culture medium are loaded in a fine plastic tube (catheter) with a syringe on one end. This is gently guided through the vagina and cervix, and the embryos are deposited into the uterine cavity. Ultrasound is used to guide the catheter during the procedure.
There is no chance of the embryos ‘falling out’ and women are advised to return to their normal routine as soon as possible.
The number of embryos to be transferred
The number of embryos to be transferred will depend on several factors such as female age, previous pregnancies and number of cycles etc.
Our policy is to transfer one or two embryos under normal circumstances. We will have discussed this with you in detail prior to treatment and again on the day of embryo transfer.
Where circumstances are unsafe or unsuitable for transfer we freeze all suitable embryos, for transfer at a later date.
Elective Single Embryo Transfer (eSET)
Elective Single Embryo Transfer (eSET) is when IVF treatment results in more than one good quality embryo, but only one is chosen to transfer to the uterus. Any remaining embryos can be cryopreserved for transfer in follow-up cycles.
Rarely a single embryo does split in two following transfer, resulting in identical twins. The chances of this occurring are very low.
We offer many advanced fertility treatments including:
- Endometrial Scratch (ES)
- Embryo Cryopreservation and Vitrification
- Oocyte Vitrification (Egg Freezing)
- Surgical Sperm Retrieval (SSR)
- Frozen Embryo Transfer (FET)
- Sperm Cryopreservation / Freezing
We partner with the Merrion Fertility Clinic and First IVF for IVF services