In Vitro Fertilisation (IVF) and Intracytoplasmic Sperm Injection (ICSI) are the two most common fertility treatments. The key difference between IVF and ICSI is how the sperm fertilises the egg.
In IVF, the egg and sperm (of which there are multiple) are left in a petri dish to fertilise on their own. In ICSI, one sperm is directly injected into the egg. It is important you do not confuse these treatments with Intra-Uterine Insemination (IUI) which is the process whereby a sperm is inserted into a woman’s womb at the most fertile point in her menstrual cycle. Whilst IUI has lower success rates than IVF and ICSI, it is much more simple and is a non-invasive theatre procedure. It is typically recommended to single women.
ICSI
ICSI as it’s thankfully shortened to, is a treatment that can be performed as part of IVF. It is specifically designed to help couples who are having trouble conceiving due to issues with sperm, such as slow moving sperm, low sperm count or abnormally shaped sperm. ICSI is similar to conventional IVF in that eggs and sperm are collected from each partner. To achieve fertilisation, a single sperm is taken up in a fine glass needle and is injected directly into an egg. The eggs are incubated and examined the following day for fertilisation. Embryos may then be transferred back into the womb of the woman two to five days after fertilisation as in conventional IVF.
Not all eggs collected will be of a high enough quality or mature enough to be suitable for injection. Also, some eggs may not survive the injection process.
As a result, the chances of successful fertilisation are much higher. It is estimated that for around half of couples struggling to conceive, the cause of infertility is sperm-related. ICSI is the most common and successful treatment for couples with male-factor infertility. This treatment offers men the chance of having their own genetic child with their partner. It is also an option for patients using frozen sperm, or who have had a previous failed cycle due to low fertilisation.
IVF
(IVF), which literally means “fertilisation in glass”, refers to assisted reproduction that takes place outside of the body. During the IVF process, eggs are removed from the ovaries and fertilised with sperm in the laboratory. The fertilised egg (embryo) is later placed in the woman’s womb.
IVF was originally developed to treat infertility caused by blocked or damaged Fallopian tubes. However, IVF is currently used to treat a variety of fertility problems that have not responded to other medical and surgical interventions. IVF is a method that has helped many women to have babies since 1978 when it was first used successfully. IVF is now an established medical procedure with over 75,000 IVF treatment cycles.
IVF involves the collection of eggs and sperm that are mixed outside the woman’s body in a culture dish. Any eggs that fertilise are called embryos and these are allowed to grow for two to five days and then the best one or two are transferred into the woman’s womb. If the treatment is successful, an embryo will implant in the lining of the womb. The woman will then be pregnant, as if she had conceived naturally.
IVF can be performed with the single egg that is produced naturally each month, but this is inefficient and has low success rates. Therefore, in the majority of treatment cycles, the woman undergoes stimulation of the ovaries with fertility hormones so that several eggs are obtained. This process is called super ovulation.
The production of several embryos means that the best quality embryos can be replaced, thus improving success rates. It can also result in the production of “spare” embryos. Good quality spare embryos may be frozen to allow replacement at a later date without the need for hormone stimulation. This maximises the chance of pregnancy from one egg collection.
How do I know which one to choose?
In terms of success rates, patients undergoing ICSI and IVF have roughly the same likelihood to conceive. Whether you have treatment with IVF or ICSI, it almost has an identical process. However, they are slightly different in how the sperm fertilises the egg. Always ensure that you are fully aware of your treatment plan, process and pricing before you begin your chosen treatment.
The results of your fertility tests and a consultation with your fertility specialist can help you decide which fertility treatment is right for you.
