In vitro fertilisation, IVF, was developed in the 1970s as a treatment for infertility due to the tubal factor. The world’s first IVF baby Louise Brown was born on 1978. Today, IVF methods are proven to be an efficient for patients with different infertility reasons both from female and male side.
IVF means that eggs and sperm are taken out of the body and fertilization takes place in laboratory conditions. The eggs and sperm are cultivated in a special incubator in which the temperature, humidity and gas content are carefully controlled to simulate the conditions in the female reproductive organs. Fertilization and the development of embryos are monitored during each phase. Usually about 70% of the eggs become fertilized and approximately 30-50% of the fertilized eggs develop into good-quality embryos. The best of these is selected for fresh embryo transfer, during which the embryo is placed in the uterus 2–5 days after fertilization. The remaining good-quality embryos are frozen for later frozen embryo transfers. 30–40% of fresh embryo transfers lead to a clinical pregnancy. Read more about Nova Vita’s IVF success rates.
During the normal menstrual cycle, one egg ripens and becomes released in the woman’s ovaries, while the other follicles that started to grow become atrophied. Before IVF, the woman receives hormonal treatment that helps more than one follicle to grow and the eggs contained in them to become ripe for fertilisation.
Hormonal treatment is planned individually for each woman. Depending on the method of treatment, it lasts 2–4 weeks. Hormones are injected under the skin. The progress of the treatment is monitored in ultrasound examinations and sometimes also by means of hormone blood tests. You can continue your normal life, work and leisure activities during hormone treatment.
Collection of eggs
Eggs are collected from the follicles of the ovary. The procedure is carried out by means of a thin needle under ultrasound observation through the vagina. During collection, the woman has short and light general anaesthesia.
On average, 10 eggs are collected at one time, but this varies on a case-by-case basis.
After the eggs have been collected, the woman’s condition is monitored at the clinic for a couple of hours. Adequate pain medication is offered. The sick leave usually lasts for the day of collection and the following two days.
Classical in vitro fertilization (IVF)
After egg collection eggs are incubated for couple of hours in incubator and sperm is washed with special gradient mediums to separate better quality sperm from non-motile sperm cells. In classical IVF procedure eggs and sperm are put together on Petri dish and fertilization of the eggs is checked on the next morning.
Intracytoplasmic sperm injection (ICSI)
Intracytoplasmic sperm injection, ICSI, is used as a treatment for infertility due to the man if the sperm count of the sperm sample is very low or if the motility of the sperm is particularly poor. This treatment is also used when normal IVF has not led to fertilisation. Before the ICSI treatment, the woman receives hormonal treatment and eggs are collected just as for IVF. Motile sperm are separated from the man’s sperm sample for intracytoplasmic injection.
In ICSI, fertilisation is aided by introducing one sperm into a ripe egg by means of a thin glass needle. The fertilisation of the eggs and development of the embryos are monitored just like in normal IVF. The treatment results of ICSI are comparable to those of IVF.
Collection of sperm from the testicular tissue
If the man has no sperm in his semen, sperm may still be found in the testicular tissue. A tissue sample is taken from the testicle after local anaesthesia. You will be on sick leave on the day of the procedure. Sperm are separated from the sample and introduced into ripe cells by means of the ICSI method. The treatment results are comparable to those obtained when using sperm separated from the semen.
Cultivation of embryos
The fertilisation of eggs is checked within 16–20 hours after bringing the egg and the sperm together. The embryo can already be placed in the uterus at this point, but after a longer period of cultivation, the embryo giving the best chance of pregnancy can be selected for transfer.
The embryos are usually cultured for 2–3 days in the laboratory. They are cultured until the mitotic phase in which the two-day-old embryos consist of four cells, and the three-day-old ones of eight cells. It is sometimes useful to continue the cultivation for 4–5 days until the blastocyst stage.
The possibility of pregnancy can be predicted on the basis of embryo development and appearance. The best of the embryos with a good prognosis is selected for fresh transfer, and the remaining good embryos are frozen for future frozen embryo transfers.
An embryo transfer is the procedure in which the embryo aged 2–5 days is placed in the uterine cavity. Embryo transfer is carried out under ultrasound observation using special catherter. Usually only one embryo is transferred at a time in order to avoid multiple pregnancies. The doctor determines the number of embryos to place after discussing the medical history and the wishes of the couple with them. Hormonal treatment continues vaginally after embryo transfer.
A pregnancy test is done two weeks after the embryo transfer. If the test is positive, the first ultrasound examination is done approximately five weeks after the embryo transfer. If the pregnancy has progressed as usual, monitoring will be provided by the maternal and child health services as in any pregnancy.
The best of the embryos produced in the infertility treatments is selected for fresh transfer, and the remaining good-quality embryos are frozen. The embryos are stored at the temperature of liquid nitrogen (-196°C) under carefully monitored conditions for any future frozen embryo transfers. If necessary, the embryos can be kept for years, but maximum for 7 years.
Frozen embryos can be transferred into the uterus at a suitable time of the woman’s own, natural menstrual cycle or during a hormone-supported cycle. More than 70% of the frozen embryos survive the thawing. Some 20–40% of frozen embryo transfers lead to pregnancy.