What is IVF?
IVF (in vitro fertilisation) is a fertility treatment where a sperm fertilises an egg outside the body. “In vitro” literally means “fertilisation in glass” which is why IVF is also called “test tube babies”.
Who might need IVF?
During a woman’s normal monthly cycle one egg grows and is released (ovulated). As this happens the fallopian tube moves to collect this microscopic egg. Meanwhile sperm must swim from the vagina, through the cervix and womb into the tube to find the egg. Once beside the egg several sperm must bind to it for one to complete its journey and enter the egg. Specialised microscopic hairs and muscle in the wall of the fallopian tube move the fertilized egg down the tube into the womb as it changes to become an embryo. Once inside the womb the embryo must find a place to implant in the womb lining and become a pregnancy.
If the egg is not fertilised by a sperm her period will start 14 days later. If the Fallopian tubes are blocked or cannot pick up the released egg, then the egg and sperm can’t meet and pregnancy doesn’t occur. If the sperms are only produced at low levels or cannot swim well they are unlikely to make it to the egg and pregnancy is unlikely to occur. There are also many other reasons why a couple may not achieve a pregnancy. There IVF is a treatment that brings eggs and sperm together in the laboratory and encourages fertilisation to happen by providing a nourishing environment.
IVF bypasses several of the natural processes of conception in the human body such as
- The role of the fallopian tubes in collecting the egg as it is released from the ovary (ovulated)
- The need for sperm to swim through the womb into the fallopian tubes to reach the egg
- The need for the fertilised egg to move down the tube and find its way into the womb
IVF can also control the complex process of a sperm entering and fertilising an egg.It provides a nourishing environment as the fertilized egg develops into an embryo. The last step of IVF is to gently transfer the embryo or embryos back inside the womb where they would have been at that time had all been working as usual in the body.
What is an IVF cycle?
Each month instead of trying for a baby during her natural cycle, a woman can have an IVF cycle instead. There are five steps in an IVF cycle:
STEP ONE – Getting ready
Once you have decided to have an IVF cycle, the first step is getting your body ready. We advise all women to start taking folic acid (minimum dose 0.4mg/day) or to take a multi-vitamin supplement that contains folic acid. Sometimes a medication such as the birth control pill or a monthly injection will be given to you to prepare your ovaries and womb for your treatment. The results of all your screening blood tests need to be available at this point.
STEP TWO – Preparing your eggs
In a woman’s natural cycle one egg grows a month. To give you a better chance of getting pregnant more eggs than this will help. To help your ovaries produce more than one egg a fertility drug (called FSH hormone) is taken by injection every day for between 8-14 days. This is carefully monitored by ultrasound scans and blood tests every few days.
Often a second drug (called Cetrotide) is needed for the last few days to prevent any eggs from being released and lost inside the woman’s body. After 8-14 days your eggs will be nicely grown and ready to be collected. At this point a special injection is given to mature your eggs so that they can be collected 34-36 hours later.
STEP THREE – Collecting your eggs
Eggs are collected by passing a needle through the wall of the vagina into the ovary guided by an ultrasound scan. It does not require surgery and is a minor procedure which takes around 30 minutes. The eggs will be collected into the needle one by one, and placed in an incubator in the fertility laboratory by the embryologist.
For the egg collection our anaesthetic doctor will give you pain killing drugs so that you are comfortable. Most women sleep through the procedure or say that they feel very little. We will need you to stay in the hospital for 3-4 hours after your egg collection until you are well enough to go home. Because of the drugs that you will have been given, you will not be able to work for the day and should not drive afterwards or sign any legal documents.
STEP FOUR – Preparing the sperm
The day that the eggs are collected, the male partner will produce a sperm sample. If a donor sperm sample is being used this will be thawed. The sperm will be washed and carefully prepared so that the healthiest sperm can be used to fertilise the eggs. If donor sperm is being used it will be thawed out and prepared.
STEP FIVE – Replacing the embryos inside the womb
Two to six days after the eggs have fertilised, the healthiest embryo or embryos are selected to be put back into the woman’s womb. This embryo transfer procedure is not painful and takes 10-15 minutes. It feels very like having a cervical PAP smear.
The number of embryos to be placed inside the womb will be carefully decided by you along with your doctor and the embryologist. If suitable, remaining embryos can be frozen in case you have further IVF treatment. After the embryo transfer it will be 9-12 days before you can find out whether your IVF cycle was a successful one by having a pregnancy test.
What is an embryologist?
An embryologist is a scientist (and sometimes a doctor) who is an expert in the fertility laboratory. Embryologists ensure the eggs are given the right environment to thrive in the IVF lab, prepare the sperm and where needed select the best sperm and inject it into an egg (ICSI). After egg collection the eggs and sperm are mixed and left to fertilise overnight. When the sperm quality is suboptimal the sperm are injected into the egg by ICSI. The next day the embryologist checks to see how many eggs have fertilised. Those that have fertilised (now called embryos) are watched carefully for another 1-4 days as they develop
What is ICSI?
ICSI (pronounced ick-see) or Intra-Cytoplasmic Sperm Injection was one of the biggest advances in fertility treatment after IVF. It is not a treatment in itself, but is used in conjunction with IVF. ICSI involves injecting a single sperm into the centre of an egg, giving it the best chance of fertilising. It is often recommended when the male partner has a very low sperm count or if other problems with the sperm have been identified.
Just like human eggs, human embryos are very delicate and so small that they cannot be seen with the human eye. Many embryos would fit on the tip of a pin. They require carefully controlled environmental conditions such as warm temperatures and the right gases and nutrients. They start as one cell and will eventually grow into the billions of cells that make up a human being.
Your embryos are placed back inside your womb anywhere between the two cell stage (day 2 of their life) or the blastocyst stage on day 5 or 6 where they are now several hundred cells.
Does IVF work?
Every year around the world thousands of babies are born after IVF treatment. However IVF treatment certainly cannot guarantee a pregnancy. Your chance of conceiving with IVF depends on several things. IVF is more likely to be successful when the woman is below the age of 35 years or a couple have been suffering with infertility for a short period of time (less than five years).
What are the risks of IVF?
IVF is usually a very safe procedure, however like all medical treatments, there are some risks.
You may experience a mild reaction to some of the fertility drugs we use including hot flushes, nausea, feeling down or irritable, headaches or restlessness and bloating.
Having a multiple birth (twins, triplets or more) is the single greatest health risk associated with fertility treatment. This is why many countries have now imposed restrictions on the number of embryos that a clinic can transfer during IVF. Multiple births carry risks to both the health of the mother and to the health of the unborn babies. The babies are more likely to miscarry, to be premature and have disabilities or cerebral palsy. For this reason we carefully guide you to decide how many embryos should be placed inside your womb.
IVF can also result in an ectopic pregnancy. This is when an embryo develops in your fallopian tube rather than in the womb, and can happen in a natural pregnancy or when you have become pregnant through fertility treatment. Rarely in more fertile women going through IVF the ovaries can over respond leading to a condition called ovarian hyper-stimulation syndrome (OHSS).
Can I have treatment with donor eggs or donor sperm?
We will usually recommend using donated eggs or sperm when we consider that treatment would be unlikely to be successful if you were to use your own eggs or sperm. This is highly likely for women over the age of 43 years. Eggs can be obtained either from someone you know who is willing to donate for you, or from an anonymous egg sharer that we can provide.
How can I make IVF more affordable?
If you are under the age of 35 years then you can apply to become an egg sharer. Becoming an egg sharer will reduce the cost of your IVF cycle. Egg sharing means that you offer to share half of your eggs collected during your IVF cycle with a couple who do not have eggs. It is a completely anonymous process and requires careful thought by both of you before you can go ahead. If you are interested please ask your clinician or nurse for more information. Not everyone is suitable and you will need to pass our strict screening process.