The subject of artificial insemination offers plenty of food for thought, although much of the discussion stems from misinformation; One of the most classic examples is the confusion that arises when talking about the two best-known assisted fertilisation methods: intrauterine insemination and IVF.
In fact, intrauterine artificial insemination refers to the medically assisted procedure that is performed “in vivo”, i.e. inserting sperm into the woman's body with the hope that fertilisation will occur.
Although intrauterine artificial insemination can also be performed on a natural cycle, in order to increase the chances of success, it is customary to stimulate the ovaries so as to cause the maturation of at least 1/3 of the follicles, monitoring the treatment with ultrasound scans that will allow us to identify the most favourable moment for insemination.
Once the most likely day has been determined, the spouse must deliver a semen sample to the laboratory (a couple of hours before insemination), which is processed in order to recover the mobile sperm by concentrating them in a small volume. They are then inserted directly into the uterus through a cannula.
This technique is quick (it only takes a few minutes) and painless, so much so that the patient is discharged immediately after insemination.
In order to increase the chances of success, the woman will take progesterone until the pregnancy test is performed and, in the event of a positive result, continue taking it.
As far as the success rates of this technique are concerned, they are around 15/20 % per attempt.
Intrauterine artificial insemination requires a minimum of 2-3 million sperm with progressive mobility.
If insemination fails after a series of 3-4 cycles , it is advisable to switch to in-vitro fertilisation (IVF).
When we talk about IVF, we mean in vitro fertilisation with embryo transfer (ET), i.e. the artificial fertilisation of oocytes with sperm in the laboratory by replicating “in vitro” what normally happens in the female tube.
In vitro fertilisation comprises four stages:
Oocyte production is stimulated with drugs to induce multi-ovulation so that more cells are fertilised, thus increasing the chances of success.
The aspiration of the oocytes will take place when they are deemed mature.
The stimulation process can be cancelled if, by ultrasound, a high number of follicles is detected, so as not to risk what is called ovarian hyperstimulation syndrome.
Then, when they are mature, the oocytes are retrieved, by ultrasound, in the operating room (after sedation), through needle aspiration.
The procedure lasts about 15 minutes, and the patient can go home after about two hours. At this point, the follicular fluid taken will be analysed in the laboratory to assess the quality and quantity of the oocytes.
On the same day that the oocyte-sperm union takes place, a sample of the spouse's semen must be available.
There are two possibilities for fertilising oocytes: placing the sperm together with the oocytes in a special culture medium (IVF) or inserting the sperm inside each oocyte by means of Intracytoplasmic Microinjection (ICSI), with the aid of a microscope, ensuring the union of oocyte and sperm.
After 16-20 hours, the number of fertilised oocytes is assessed under the microscope; subsequently, the oocytes will begin to divide, giving rise to embryonic development, during which they will be assessed the quality of the embryos and, consequently, a decision will be made as to which will be transferred into the uterus, any good quality supernumerary embryos will be cryopreserved for possible subsequent attempts.
The process of embryo reinsertion is simple and quick and does not require any anaesthestic. The embryos are placed back into the uterus via a thin plastic cannula, through the cervical orifice, under ultrasound supervision, to ensure correct positioning within the uterine cavity.
In the event that one or both parents are carriers of genetic abnormalities, or one wants to be sure of transferring embryos with a normal chromosome map (karyotype), embryo biopsy with pre-implantation genetic testing, known as PGTcan be used.