The IVF breakthrough in the late 1970s was the most important advance in treating infertility. In vitro fertilisation – the so-called “test tube baby” technique – quite literally means fertilisation in glass (vitro).

With natural fertilisation, a single egg develops in one of the ovaries each month. It grows in a fluid-filled cyst or follicle for about a fortnight before it is released – this is known as ovulation.

The egg enters the fallopian tube and meets the sperm. Fertilisation creates a fertilised egg or embryo. As the embryo passes down the tube to the womb (uterus) its cells divide and grow. This is known as cleavage. If the embryo implants into the uterus lining, a pregnancy is established a week or so after ovulation.

IVF was originally devised to help women with damaged fallopian tubes by bypassing the damaged or blocked area and placing the embryo directly in the uterus. The eggs are removed from the ovary just before ovulation. Eggs and sperm are mixed together in the laboratory. If fertilisation occurs, the embryo is transferred into the uterus two or three days later. Today IVF and its developments are widely used to treat both male and female disorders.

IVF is performed in five main stages - egg production, monitoring egg production, egg recovery, insemination and embryo transfer.

Egg Production

As a first step, the ovaries are stimulated by drugs to achieve egg production. Ovarian function is suppressed with buserelin (to prevent spontaneous ovulation) and the ovaries stimulated with gonadotrophins. Most women carry out the injections themselves.

The regime starts with daily buserelin injections a week before the woman’s period begins. Menstruation occurs as usual and daily gonadotrophin injections begin about two weeks after the first buserelin injection. The two injections continue for approximately 10-12 days until the woman is ready for egg collection.

Monitoring egg production

Ultrasound scans and bloods tests are performed to monitor egg production.  

Egg recovery

Eggs are collected using a vaginal ultrasound guided technique under sedation or a general anaesthetic.

Insemination

On the same day as the eggs are collected, the partner provides a sperm sample and the most active sperm are selected and mixed with the eggs in the culture medium. They are then incubated overnight and checked the next morning for signs of fertilisation.

Embryo transfer

The best of the fertilised eggs – embryos – are replaced in the uterus under ultrasound monitoring. This is carried out during a walk in, walk out admission.