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In Vitro Fertilisation (IVF) is a process in which an egg is surgically removed from the ovary and fertilised outside the body . One in seven UK couples trying for a baby experience delays in conceiving. Conception is a complex process involving many factors, and if one of these factors is impaired, infertility can result. IVF is one method used to help people with fertility problems to have a baby.
Approximately six thousand babies are born as a result of IVF each year. However, it should be noted that the procedure has an average success rate of only 15%.
The typical cost of one IVF cycle at a private clinic is 2,000. However, from April 2005, all Primary Care Trusts (PCTs) should be offering at least one cycle of IVF (In Vitro Fertilisation) treatment on the NHS to infertile couples. Women must be aged between 23 and 39 to qualify for free treatment. In addition, they must either:
have a specific problem such as absence of sperm or blocked fallopian tubes, or
have been unable to conceive for three years despite regular intercourse and no identifiable problem.
Under further recommendations from the National Institute for Clinical Excellence (NICE), eventually three free cycles of IVF should be offered, but a timescale for implementing these guidelines has not yet been announced.
When should it be done?
It is normally advised that couples considering IVF have been trying for a baby for one year before approaching their doctor about assisted conception. At this stage, a medical evaluation will be required to determine the situation before any treatment begins. This may include physical examinations; tests to check blood hormone levels, ovarian function and sperm quality; x-rays of the reproductive organs; and perhaps a laparoscopy to pick up anything that an x-ray may miss, such as blockages or adhesions in the pelvic cavity.
One of the main factors influencing the outcome of IVF treatment is the age of the woman whose eggs are used, as the quality of the eggs declines as the woman gets older. The rate of birth defects, chromosome abnormality or miscarriage also rises with maternal age.
Couples considering IVF must undergo an assessment at a fertility clinic before any treatment begins. Pre-conception programmes, e.g. those offered by the UK charity Foresight, help people with fertility problems to optimise their health before treatment starts.
Why is it necessary?
Infertility in one third of cases can be attributed to factors affecting women, such as problems connected to egg release, blockages in the fallopian tubes, or structural defects (congenital abnormalities) of the uterus. Another third of cases involve factors affecting men, which may include a low sperm count (oligospermia), poor sperm motility and/or lifespan, or azoospermia where no sperm cells are produced. The remaining third of infertility cases can be attributed to fertility issues in both partners, or to reasons unknown.
How is it performed?
The main IVF technique was developed in the 1970s. This involves giving the woman fertility drugs to stimulate egg production, and then surgically retrieving the eggs from the ovaries. She is then given hormones to prepare her uterus for pregnancy, while the eggs are fertilised with the sperm in a laboratory. The embryos are then implanted into the womans uterus, and if all goes well a normal pregnancy is achieved.
The Human Fertilisation and Embryology Authority's code of practice for clinics, states the number of embryo transfers should be limited to two for most women. However,women over 40, whose chances of a baby are smaller may have more than two embryos transfers.
IVF procedures developed more recently include Intra-cytoplasmic Sperm Injection (ICSI). This helps those men for whom the standard IVF technique would fail, e.g. if their sperm are unable to penetrate the egg, to achieve pregnancy with their partner.
Egg selection enables only the healthiest eggs to be taken from the ovaries for fertilisation. It can be useful for women with diminished number and quality of eggs. Procedures such as sperm washing can also be carried out to only retrieve sperm strong and healthy enough for inclusion in IVF techniques. This is particularly successful with men who have a low sperm count.
New assisted conception techniques are constantly being developed, and existing procedures refined. For example, 3D ultrasound can now be used to detect pre-pregnancy fertility problems, such as blocked fallopian tubes.
Undergoing IVF or other assisted conception procedures can be emotionally and physically draining. It is important that couples are offered counseling where appropriate, for example to understand the implications of treatment, or as a means of support at a critical time (e.g. if an IVF cycle has failed).
Assisted conception brings several risks.
The diagnostic and treatment procedures can involve discomfort, particularly for the woman undergoing IVF, who may experience side effects from fertility drugs involved and may find the egg retrieval uncomfortable.
Ovarian hyperstimulation syndrome (OHSS) is a rare but known side effect of IVF. It occurs when the fertility drugs given to stimulate egg production in the woman are so successful that the ovaries cannot cope with the increased number of eggs. A mild incidence can cause pain and bloating. If the overstimulation is severe, blood clots, kidney damage and twisting of the ovaries may occur, and monitoring in hospital will be required. OHSS can jeopardise the progress of the treatment cycle.
Some assisted conception techniques carry an increased risk of ectopic pregnancy, where the fertilised egg implants in the fallopian tubes instead of the uterus. There is a greater risk of multiple gestation, e.g. twins or triplets, as the chances of IVF success are maximised by more than one embryo being put back into the womb. This has associated dangers, such as a higher chance of stillbirth, miscarriage & premature delivery.
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