Sign In

Lab interventions help create life


An assisted conception technique, IVF (in vitro fertilisation) involves fertilising the woman’s eggs in a laboratory petri dish – “in vitro” means “in glass”.

IVF treatment begins with the woman being given drugs to stop her natural menstrual cycle. Once her cycle has been stopped, she takes fertility drugs to stimulate her ovaries to produce eggs. A woman would usually produce one egg per month, but with IVF drugs, she will produce about ten to fifteen so that the best ones can be selected.

After about 12 days, women are given another hormone to mature the eggs. A couple of days later, the eggs are removed at the clinic through the vagina by means of an ultrasound guided probe.

On the same day that the eggs are removed, the man will need to provide a sperm sample. An embryologist puts the sperm and viable eggs together in a petri dish to fertilise the eggs. Two to five days later, the aim is that some of the eggs will have fertilised and, if so, they now called embryos. One or two of these embryos will be placed in the womb and if all goes well, the embryo develops to become a full-term, successful pregnancy and a healthy baby. Other viable embryos can be frozen to preserve them for later use.

  • Success rate: about 25 per cent of IVF treatments using a woman’s own fresh eggs results in a live birth.


If a man has fertility problems, such as a low sperm count or unhealthy sperm, then ICSI (intra-cytoplasmic sperm injection) is often used. This is a treatment where a sperm is injected directly into an egg in the laboratory. ICSI can also be used if the male partner has difficulty getting an erection or ejaculating.

In a similar way to IVF treatment, the woman is given drugs to stimulate her ovaries to produce a number of eggs. The eggs are removed and, a few days later, two or three viable embryos are transferred back into the womb.

What happens at the lab, however, is different. The man gives a sperm sample, from which an embryologist selects the healthiest sperm and then injects a single healthy sperm into each viable egg. If the man is not able to produce a sperm sample, for example if he has erection problems, doctors can remove sperm from his testicles using a fine syringe. After two to three days, between one and three of the healthiest embryos are placed in the woman’s womb.

ICSI was introduced in 1992. In 2011, 40,340 fresh embryos were transferred during ICSI treatment. It is quite an invasive treatment and isn’t usually used as a first option for couples with unexplained infertility.

  • Success rate: about 28 per cent of ICSI treatments using a woman’s own fresh eggs results in a live birth.


A simpler technique than IVF and ICSI is IUI (intrauterine insemination). You may have heard it referred to as “artificial insemination”.

Before IUI treatment can go ahead, the woman needs to have a fallopian tube patency test. This confirms she has a healthy pelvis and there are no blockages in the fallopian tubes that might stop the sperm meeting the egg. The man also needs to have tests to ensure there are no problems with the health or number of sperm he produces, which could affect how successful treatment can be.

The woman takes fertility drugs to trigger the production of one or two eggs. The partner or sperm donor produces a sperm sample which is then purified in the lab so that just the most healthy and fast-moving sperm remain. The sperm is then injected into the woman’s womb, at the most fertile time of her cycle. Unlike IVF and ICSI, fertilisation takes place inside the women’s body. It also avoids using the stronger fertility drugs used in IVF and ICSI, which can cause complications, such as a swollen and painful ovary.

The National Institute for Health and Care Excellence (NICE) recently recommended dropping IUI as an NHS treatment because of its low success rates.

  • Success rate: for women under the age of 35, 16 per cent of IUI cycles result in a birth and for women aged 43 to 44, 1 per cent of cycles result in a birth.


The use of spare embryos generated by IVF or ICSI is known as FET (frozen embryo transfer). If the frozen embryos are still healthy and able to be used for fertility treatment, they can be thawed and transferred to the woman’s womb at a later time if an IVF or ICSI cycle didn’t work, or a successful couple want to have more children later on.

An FET cycle can be either stimulated or unstimulated. Stimulated treatment is when the woman is given injections of hormone to thicken the lining of her womb so that it is more likely to accept the embryo.

Unstimulated treatment relies on the woman’s normal menstrual cycle. The clinician will monitor the woman’s womb using an ultrasound scan and ovulation predictor kits to try and work out when the womb is most likely to be ready to accept an embryo.

According to the UK regulator, the Human Fertilisation & Embryology Authority, in 2010 there were 10,548 cycles using thawed embryos created from a woman’s own eggs. In 2011 there were 11,283 FETs, a 7 per cent increase.

  • Success rate: frozen embryo transfer, using a woman’s own eggs, has an overall success rate of 25 per cent. Women who are 45 or older can expect a success rate of around 15 per cent.