Intracytoplasmic sperm injection (ICSI) is very similar to In Vitro Fertilization (IVF) in that gametes (eggs and sperm) are collected from each partner. The difference between the two procedures is the method of achieving fertilization.
In In Vitro Fertilization (IVF), the eggs and sperm are mixed together in a dish and the sperm fertilises the egg ‘naturally’. Intracytoplasmic sperm injection (ICSI) is when a single sperm is injected into an egg.
Intracytoplasmic sperm injection (ICSI) is used when the sperm cannot penetrate the egg on its own. Intracytoplasmic sperm injection (ICSI) is recommended for couple’s who have been diagnosed with male fertility issues such as low sperm count, low sperm morphology or motility, anti-sperm antibodies or have previously had a vasectomy or unsuccessful vasectomy reversal. Intracytoplasmic sperm injection (ICSI) does not require large numbers of sperm cells or good sperm quality to achieve fertilization of an oocyte.
Chances of success vary between patients, particularly according to the age of the woman, but on average about 25% of patients will have a baby after one attempt at Intracytoplasmic sperm injection (ICSI).
Intracytoplasmic sperm injection (ICSI) treatment cycle is exactly the same as a conventional In Vitro Fertilization (IVF) cycle.
- Stimulation of the ovaries to encourage development and maturation of the eggs.
- Retrieval of the eggs.
- Fertilisation of the eggs and culture of the embryos.
- Transfer of the embryos back into the uterus.
Twelve days after the embryo transfer, the woman is given a pregnancy test. A positive pregnancy test means that an embryo has implanted.
One cycle of Intracytoplasmic sperm injection (ICSI) takes between four weeks and six weeks to complete.
Pre-implantation Genetic Diagnosis (PGD)
Pre-implantation Genetic Diagnosis (PGD) is the diagnosis of genetic and chromosomal alterations in embryos before they are implanted, in order to ensure that children are born free of hereditary diseases. This assisted reproduction technique always requires in-vitro fertilisation treatment (IVF) with sperm microinjection (ICSI), so that the embryos are available in the laboratory.
Candidate for Pre-implantation Genetic Diagnosis (PGD):
- Anyone who has a known inherited gene defect in their family that causes a genetic disease
- Couples, and women over the age of 40 who have not managed to get pregnant naturally.
- Couples who have suffered repeated miscarriages and couples who have not had any success with assisted reproduction due to a paternal anomaly.
- Couples who have been two or more unsuccessful in-vitro fertilisation treatment (IVF) attempts
There are 8 steps for Pre-implantation Genetic Diagnosis (PGD):
- Step 1: Stimulation of the ovaries
In order to create embryos for genetic testing, the ovaries have to be artificially stimulated using hormones to produce several eggs at the same time.
Because a significant number of a couple’s embryos are likely to be affected by the genetic or chromosomal abnormality, a large number of embryos need to be created for the best chances of success.
- Step 2: Collection of eggs from the ovaries
At the appropriate time, the eggs are removed in during a surgical procedure known as egg retrieval. Once the eggs are removed, they are inspected to determine which are mature and normal appearing.
- Step 3: Insemination/injection of sperm
Fertilisation during Pre-implantation Genetic Diagnosis (PGD) will be done either by:
In Vitro Fertilisation (IVF): Sperm and eggs are placed together in a culture dish to allow fertilisation to occur.
Intracytoplasmic Sperm Injection (ICSI): A single sperm is injected in the center of an egg. This technique is used for conditions caused by a single faulty gene.
- Step 4: Fertilisation
The morning after injection/insemination of the sperm, the embryologist carefully examines each egg to see if fertilisation has occurred.
- Step 5: Embryo biopsy
The eggs that were successfully fertilised are grown in the laboratory for 5-6 days when the embryo forms what is called a blastocyst of about 100-150 cells. At this stage trophectoderm biopsy (the cells which will form the placenta) takes place.
This technique is highly specialised and can only be carried out by embryologists who have a special license from the Human Fertilisation and Embryology Authority (HFEA).
The removal of these cells should not harm the embryo.
- Step 6: Embryo Testing
The cells are tested to see if the embryo from which they were removed contains the abnormality that causes the genetic condition.
- Step 7: Embryo Transfer
Only those embryos that do not have the specific genetic condition that was tested for will be transplanted into the woman’s uterus. Usually one embryo will be transferred to the uterus at any one time to avoid the possibility of multiple births (more than one baby in a pregnancy).
Any suitable remaining unaffected embryos will be frozen for later use.
Those embryos that are affected by the inherited condition are allowed to perish or couples are asked if they would consider allowing these embryos to be donated for research and training.
- Step 8: Pregnancy Test
Twelve days after the embryo transfer, the woman is given a pregnancy test. A positive pregnancy test means that an embryo has implanted.
