In vivo fertilisation techniques

In homologous intrauterine insemination, the seminal liquid of the partner, previously treated in the laboratory to obtain an adequately concentrated selection of spermatozoa, is deposited directly inside the uterine cavity (IUI) via a catheter, at the moment of ovulation. The fertile day is identified by LH and Estradiol level in the blood and ecographic monitoring of the ovulation.
In selected cases, the insemination can be combined to ovary stimulation to obtain a multiple follicle growth, thereby increasing the probability of success.
In heterologous intrauterine insemination, the same procedure is carried out with donor’s seminal liquid as indicated.

The GIFT procedure (Gamete Intra Fallopian Transfer) is a particular technique in which the spermatozoa and eggs are placed in a tube, where the in vivo process of fertilisation normally takes place.
The preparation of the patient is similar to the fertilisation technique illustrated in the in vitro fertilisation technique, but the operation is carried out in the operating room by laparoscopy and under general anaesthetic at the Day Hospital. Also in this case, the partner’s or donor’s seminal liquid is used on the basis of what has been indicated.

In vitro fertilisation technique

A sequence of treatments is necessary to be able to carry out in vitro inseminations, such as: ovulation induction, sampling of the oocytes, in vitro fertilisation according to various procedures, the development of the embryo under culture and its transfer to the uterus.
During ovulation stimulation, medicines are utilized to stimulate the ovaries to produce more mature oocytes. More fertilised eggs can be obtained and therefore a greater possibility of pregnancy by repeating the embryo transfer several times. The timing of the treatment is a crucial element in carrying out assisted fertilisation. Also in this case, LH and Estradiol plasmatic level,in combination with ecographic controls establish when the follicular maturation process has occurred (approximately 12/24 hours before ovulation). At this point, an HCG injection is given, simulating the ovulatory peak of the LH, and bringing the eggs to final maturity after 34/36 hours.
The oocytes are taken from the follicles, under ecographic guide, via aspiration with a special needle positioned on the trans-vaginal probe. The aspiration of the eggs from the ovary occurs under local anaesthetic and lasts some minutes. The eggs obtained are taken to the laboratory for the successive fertilisation by the male sperm. In the IVF procedure, (In vitro Fertilisation and Embryo Transfer), the partner’s or donor’s seminal liquid, depending on the analysis, is treated to select the spermatozoa with greatest mobility. The gametes (eggs and spermatozoa) are then cultivated on culture medium and the fertilisation spontaneously occurs in vitro.
The ICSI procedure (Intracytoplasmic Sperm Injection) can be carried out as an alternative to the IVF procedure; this technique consists of injecting a single spermatozoa inside the egg. It is a treatment advised in the cases of important male sterility factors. After approximately 16/20 hours it is possible to verify if fertilisation has occurred by noting the formation of fertilised oocytes. Two fertilised eggs are maintained under culture for 48/72 hours and then transferred to the uterus at the embryo stage (4/8 cells). The remaining fertilised eggs are cryopreserved for possible other transfer to the uterus.

ICSI is also indicated to fertilize cryopreserved oocytes.
Their fertilisation is achieved by a microinjection of a single spermatozoon (ICSI) inside the egg. Because of their structure, the oocytes have less resistance to freezing and thawing procedures and therefore the possibility of success of this solution is notably less than an ICSI with freshly-collected eggs.
The Transfer procedure is the insertion into the uterus of embryos (a maximum of two) that are adequately developed in vitro. The transfer occurs via the vaginal tract utilizing a fine catheter, it’s a painless procedure that lasts just few minutes.
The transfer normally occurs when the embryo has reached the stage of 4-8 cells or 48/72 hours after the sampling of the eggs.
In the case of transfer of cryopreserved fertilised eggs, the eggs are thawed and maintained under culture for 1 or 2 days before the transfer.

In certain cases where there is a lack of spermatozoa in the seminal liquid, it is opportune to search for them at epididymal or testicle level. Therefore, surgical sperm recovery techniques are practiced, such as MESA (Microsurgical Epididymal Sperm Aspiration) or TESE (Testicular Sperm Extraction). Both operations are carried out in the operating room under general anaesthetic in the Day Hospital.