STEP 1 – Ovulation Induction and Monitoring
Hormone drugs are given to the woman to increase the number of eggs developing in her ovaries. Fertility specialist doctors keep an eye on the eggs' development by using the results from blood tests and ultrasound scans. At the appropriate time, maturation of the eggs is triggered by another drug so the doctor can retrieve the woman's eggs at the right time. Usually the eggs will be used ‘fresh’, but sometimes eggs are frozen to be thawed and used later.
STEP 2 – Sperm Collection
A sperm sample (pictured right) is produced by the man and given to the laboratory. If a man doesn’t have any sperm in his semen, sperm can sometimes be surgically retrieved. Sometimes the sperm will be used ‘fresh’, and sometimes it will be frozen to be thawed and used later.
STEP 3 – Egg Collection
The doctor uses an ultrasound scan and a long needle to collect eggs from the ovaries. This procedure takes about 15 minutes and pain relief is used to help with any discomfort.
STEP 4 - Fertilisation
The embryologist takes the eggs and sperm and places them into a solution containing nutrients in a Petri dish, which is placed in an incubator. If / when a sperm joins the egg, fertilisation has occurred.
STEP 5 – Embryo Development
All going well an embryo will develop. This is a pronuclear embryo that is 1 day old (pictured below left). Embryos are then cultured for a further 1-5 days. During this time a series of checks helps identify the embryo(s) with the greatest developmental potential. Embryos may be left to develop or frozen to be thawed and used later.
Below middle is pictured a two cell embryo that is 1-2 days old .
1 Cell Embryo 2 Cell Embryo 8 Cell Embryo
STEP 6 – Embryo Replacement
The embryo continues to develop into an eight cell embryo (pictured above right) at 3 days old. This is a normal pace of development, and sometimes embryos are replaced back into the uterus on this day.
By 4 days the embryo forms a morula (pictured below left) which means Mulberry in Latin - simply because it looks like a berry.
By day 5 the embryo has developed into a blastocyst (pictured below middle). Nowadays, it is increasingly common to replace blastocysts into the uterus. Usually one or, if the woman is older, sometimes two embryos are selected for transfer back into the uterus. In the past, two or three embryos were replaced at the same time to increase the chance of pregnancy. That also increases the chance of twins and even triplets. That is why so many IVF-lings from earlier years are twins.
Morula - 4 day old Embryo | Blastocyst | A Embryo 'hatching'
STEP 7 - Pregnancy
By day 6 the embryo is in the uterus and it will ‘hatch’ (pictured above right) - which literally means it will pop out of its shell. It needs to do this in order to implant in the uterus.
14 days after the original egg collection the woman has a blood test to check for signs of pregnancy.