In vitro fertilization or IVF is an assisted reproduction technique that consists of practicing fertilization, that is to say, a meeting of spermatozoa and ovum in the laboratory, in vitro, therefore outside the woman’s body.
In vitro fertilization is a technique used by couples wishing to have a child who is facing a problem of infertility.
The man’s sperm is placed in the presence of the woman’s egg outside her body, in the laboratory, then the embryo is reimplanted into the uterus of the future mother.
Medically assisted procreation (PMA) brings together a range of methods used to help a couple have a child: artificial insemination, ovulation stimulation, in vitro fertilization, etc. These techniques are practiced by specialized gynecologists trained in these methods in a clinic or hospital.
Approximately 330,000 couples suffer from infertility in Canada, i.e. between 10 and 15% of adults of childbearing age (Data from the Association of Obstetricians and Gynecologists of Quebec) In France, nearly one in 6 couples are affected by infertility.
When to use in vitro fertilization?
When a couple fails to conceive a child, the first step is to consult a doctor who can assess the fertility of the man and the woman. After a health assessment and physical examination, a series of diagnostic tests may be performed.
When possible, the doctor first treats the infertility of the woman or the man to allow them to recover their natural fertility.
When it is not possible to treat infertility, and when possible, simple methods are practiced to start a pregnancy: stimulation of ovulation (prescription of drugs that trigger ovulation) or artificial insemination for example.
In vitro fertilization is only offered to couples who cannot benefit from simpler methods or for whom simpler methods of treatment or medically assisted procreation have failed.
In vitro fertilization is the standard treatment for women or men who have been diagnosed with:
- missing or blocked tubes;
- male infertility (low sperm motility or low sperm count) that could not be cured.
When treatments have failed, IVF is also offered for cases:
- endometriosis;
- unexplained infertility (6% of infertility cases);
- malfunction of the ovaries requiring oocyte donation.
In vitro fertilization can also be performed for couples carrying a genetic anomaly that can lead to a serious illness, to be able to choose an unharmed embryo.
In vitro fertilization can be used by a couple who could not conceive without egg donation or embryo donation.
History of IVF: Who is the first baby resulting from IVF?
Louise Brown is the first baby resulting from in vitro fertilization. She was born on July 25, 1978, in England. Her parents, Lesley and John Brown had been trying for a child for 9 years but were unsuccessful because her mother’s fallopian tubes were blocked.
Two Cambridge University doctors, physiologist Robert Edwards, and gynecologist Patrick Steptoe had been working on a revolutionary technique for 10 years. They tried to combine eggs and sperm in a test tube to obtain an embryo to re-implant it into the maternal uterus.
Their attempt at in vitro fertilization turns out to be a success. The first test-tube baby is born! Louise Brown is still alive today and even gave birth to a child naturally.
Dr. Robert Edwards was awarded the Nobel Prize for Medicine in 2010 for the development of in vitro fertilization.
IVF Success Factors
The success of an in vitro fertilization treatment depends on various factors such as the age and lifestyle of the woman and the man, the cause of infertility, the number of embryos transferred during fertilization, and the number of cycles carried out.
Overall, approximately 27% of in vitro fertilization cycles will result in a viable pregnancy. The chances of success increase for a greater number of cycles performed. It is usually recommended not to undertake in vitro fertilization after the age of 42.
In France as in Belgium, IVF is covered by Health Insurance or Health Insurance until a woman is 43 years old. After 40 years, only 4 to 5% of attempts lead to a birth. The quality and the decrease in the number of oocytes are in question.
Stimulation of the ovaries
The first step is to give the woman hormone therapy, usually, a GnRH agonist (Gonadotropin-Releasing Hormone) to put the ovaries to rest (see medications section), eg Decapeptyl®, Suprefact®, Enantone® Synarel ®, or Lupron®.
The treatment then aims to increase the number of follicles produced by the ovaries and to control the moment of ovulation. The woman must receive injections of gonadotropins with FSH or LH activity to stimulate the follicles to lead them to maturation and allow them to produce several oocytes.
These are, for example, Puregon®, Gonal F®, Fostimon® Metrodin-HP®, Bravelle®, Humegon® Ménopur® Merional® Repronex® Fertinex® Fertinorm®, Humegon® Ménopur® Merional® Repronex® Fertinex® Fertinorm®, Elonva ®, Luvéris®… When the follicles have grown enough and the hormone levels are adequate, ovulation is triggered by an injection of the hormone HCG (Human Chorionic Gonadotropin), for example, HCG endo 1500®, HCG endo 5000 ® (Fr), Pregnyl ®, Choriomon®, Profasi-HP®, Chorex®, Novarel®, Ovitrelle® Ovidrel®…
Pelvic ultrasound and blood tests are performed at each stage to assess follicle growth.
More follicles, more eggs…
A woman’s ovaries usually produce and release only one mature egg per cycle. While this is sufficient for normal conception, for successful in vitro fertilization ideally more mature eggs are needed.
It is therefore necessary to stimulate the patient’s ovarian activity more strongly than usual. The drugs administered during an in vitro fertilization treatment cause the development of several ovarian follicles, thus increasing the possible number of eggs, and therefore the chances of obtaining an implantable embryo.
Collection of mature oocytes
After 32 to 36 hours of hormonal stimulation, the mature oocytes are removed using a small tube and a needle that is introduced into the vagina. This procedure is performed under local or general anesthesia with ultrasound control because it can be very painful. The oocytes are then selected in the laboratory.
The semen is collected a few hours before (or thawed the same day), and the sperm are separated from the seminal fluid and stored at 37°C.
Fertilization
A few hours after their collection, the spermatozoa and the oocytes are placed in contact in a culture liquid for several hours at body temperature. The motile sperm come spontaneously, without outside help, into contact with the oocyte. But only one sperm will fertilize this one. In general, on average, 50% of the oocytes are fertilized.
The fertilized eggs (or zygotes) begin to multiply. In 24 hours, the zygotes become embryos of 2 to 4 cells.
Embryo transfer
2 to 5 days after fertilization, one or two embryos are transferred to the woman’s uterus. Embryo transfer is a simple and painless procedure performed using a thin, flexible catheter introduced vaginally into the uterus. The embryo is deposited inside the uterus and develops there until it is implanted.
After this stage, the woman can usually resume her normal activities.
One or more embryos (called supernumerary) can also be preserved by freezing for later trials. Subsequently, the doctor can give hormonal medical treatment, and of course orders for pregnancy tests to see if IVF has been effective.
Several cycles of treatment are sometimes necessary before the pregnancy succeeds. And unfortunately, some couples do not get pregnant despite several attempts. Advice before IVF:
- stop smoking (male and female!), as this greatly reduces the chances of getting pregnant;
- exercise and aim for a healthy weight. It helps to have good fertility;
- for women: take vitamin B9 before becoming pregnant, as this reduces the risk of malformation in the unborn child;
- get vaccinated against the flu (it can cause miscarriages).
