In vitro fertilization, or IVF, is a medical procedure used when other therapies to achieve pregnancy do not work. IVF is a safe treatment that has been used successfully for more than 40 years. For its development, Dr Robert Edwards was awarded the most prestigious honour in 2010 - the Nobel Prize in Medicine.
In vitro fertilization (IVF) is a procedure recommended after an exhaustive diagnosis of infertility. It is performed when the cause of conception problems is:
No possiblity of safe ovulation
Male factor (including ICSI with sperm retrieved from a testicle or epididymis in the case of obstructive azoospermia)
Carrier HIV or HCV status of one of the partners
Diminished/diminishing ovarian reserve
Treatment failure using other methods
The presence of unexplained causes of infertility
IVF is always preceded by a thorough examination of both partners. The treatment itself consists of several stages: it begins with ovarian stimulation with the help of hormonal drugs, strictly controlled by the attending physician. Next, reproductive cells are taken from both partners and combined under laboratory conditions. The resulting embryos are cultured for several days. The final step in the procedure is the delivery of the embryo into the uterine cavity.
In vitro fertilization (IVF/ICSI) is preceded by several days of hormonal stimulation. An appropriate stimulation protocol is selected for each patient, depending on the results of hormonal tests, age, and obstetric-gynaecological history. During stimulation, drugs are given to suppress the pituitary gland (i.e. the patient's own hormonal activity) for a period of time and then drugs are given to stimulate ovarian follicle growth are turned on.
The stimulation takes place under ultrasound control, which means that it is necessary to monitor the growth of the follicles every few days while taking the medication. The level of hormones (estradiol and progesterone) in the blood is also observed. When the follicles in the ovaries reach an appropriate state of maturity, the patient takes a drug to induce ovulation, and, 36-37 hours after the administration of the drug, the procedure of collecting oocytes takes place. Usually several to a dozen oocytes are taken.
On the day of the puncture, the patient should come to the clinic fasting. The oocyte retrieval itself involves puncturing the ovaries through the vagina, under ultrasound guidance and short-term general anaesthesia. The procedure takes about 10-20 minutes. Immediately after the procedure, the fluid with oocytes is delivered to the IVF laboratory, and the patient is awakened and stays in the recovery room for about an hour. Complete psychomotor efficiency returns about 30-60 minutes after the procedure.
The man donates semen by masturbation on the day of the procedure. It is recommended that he has a 3-7 day break in sexual intercourse before this donation. Previously frozen semen or semen from an anonymous donor may also be used for insemination.
Depending on the indication, fertilization may proceed in two ways:
In vitro fertilization (IVF):
Approximately 2-4 hours after the egg cells are collected, properly prepared sperm is added to the cells. The cells are then placed in a special culture medium in an incubator at a temperature of 37 degrees Celsius, elevated carbon dioxide concentration and reduced oxygen concentration. The effectiveness of classical IVF reaches 25-45% of pregnancies per embryo transfer.
Approximately 2 hours after collection, the oocytes are cleared of surrounding follicle cells. A single sperm is inserted into each egg cell using a thin pipette. The cells are then placed in a special culture medium in an incubator at 37 degrees Celsius with elevated carbon dioxide and reduced oxygen.
On the following day, i.e. approximately 18 hours after fertilization, it is evaluated whether the fertilization process has been successful. A sign of normal fertilization is the presence of two pre-nuclei in the egg cell - a female and a male, as well as the presence of two directional bodies indicating that the oocyte has completed meiotic division. As a result of the technique of ICSI, about 70-80% of the cells fertilize correctly.
After another hour of culture, the fertilized cells (zygotes) begin to divide, the so-called furrowing stage. Two days after the puncture, properly developing embryos reach the 2-4 cell stage, and three days after the puncture, they reach the 6-8 cell stage. In each embryo, the number of cells and the morphology of the embryo are determined.
Between the second and fifth day of culture, 1-2 embryos are introduced into the uterine cavity using a special catheter. The embryotransfer procedure is painless, is performed without anesthesia, under ultrasound guidance, with a filled bladder. After the transfer, the patient remains in the gynecological chair for about 20 minutes. With a larger number of embryos obtained it is usually suggested to perform the transfer on the fifth day of culture, when the embryos have already reached an advanced stage of development - blastocyst.
All embryos that were not given during embryo transfer and have reached an advanced stage of development (called the blastocyst stage) on the fifth or sixth day of culture are frozen. It is important to remember that not every fertilized cell will develop into a blastocyst, as some embryos do not develop properly and stop during subsequent divisions and then degenerate.
Normal embryos are frozen using the currently most effective vitrification method and stored in liquid nitrogen for administration during subsequent embryotransfers.
The freezing process is so safe that the percentage of pregnancies after embryiotransfers of frozen embryos is the same as after embryiotransfers of "fresh" embryos.
The patient takes medication containing progesterone for the next 10 days. This is called luteal phase supplementation and is intended to help the embryo implant and maintain an early pregnancy. After this time it is advisable to do a HCG test from the blood and consult the further procedure with the doctor in charge.
Interested in what happens in the in vitro lab "from egg to embryo" and what the embryology work lab looks like? Take advantage of the opportunity to participate in our free webinar with an embryologist.
We are pioneers in the use of the RI Witness safety control system. It involves a unique way of labeling germ cells and embryos, which guarantees their error-free identification at every stage of laboratory operations and storage.