Let’s talk about medically assisted procreation through an in-depth study by the Istituto Superiore di Sanità.
The medically assisted procreation (MAP) it is a set of techniques, more or less complex, which couples who have infertility problems, i.e. difficulties in spontaneously conceiving children, can undergo. Since 1978, the date on which the first girl was born in England with the use of PMA, the techniques have developed and spread all over the world and, to date, more than 5 million children have been born thanks to artificial insemination.
In Italy, medically assisted procreation techniques have been divided into three levelsdepending on their degree of invasiveness on the body and/or their complexity:
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Level I, techniques such as intrauterine insemination (IUI), simple and minimally invasive Level II and III, procedures such as in vitro fertilization with embryo transfer (IVF) and intracytoplasmic single sperm injection (ICSI), plus advanced or complex
All the procedures described can use embryos e gametes (male sperm and female oocytes) “fresh” or so-called techniques of cryopreservation. Cryopreservation involves freezing and storing in liquid nitrogen at very low temperatures, equal to -196°C, of spermatozoa, oocytes or embryos, in order to keep them alive for a prolonged time, which are thawed at the time of their use.
Cryopreservation can also be applied to donated gametes. Gamete donation is used when one or both partners in the couple suffer from a disease that does not allow the use of their own cells. Based on the specific needs of each couple, the specialist doctor will recommend the most suitable procedure. In fact, there is no one technique that is better or less effective than the other. The doctor will always have to take into consideration the age of the woman as the female fertility decreases over the years due to an irreversible reduction in the quantity and quality of the oocytes present in the ovaries.
In Italy, the application of assisted reproduction techniques is regulated by law n. 40 of 2004. At theHigher Institute of Health is active a PMA National Register, which collects, analyzes and publishes data relating to the application, effectiveness, safety and results of these techniques. All public and private PMA Centers (including those affiliated with the National Health Service) are registered in the Register.
Level I techniques
Level I techniques include ovulation monitoring, ovarian stimulation and insemination.
Artificial insemination – It is the most widespread of the basic techniques of medically assisted procreation.
In artificial insemination procedures, sperm can be deposited in the vagina (intravaginal insemination, IVI), in the cervical canal (intracervical insemination, ICI), in the fallopian tubes (intratubal insemination, ITI) or in the abdomen (intraperitoneal insemination, IPI) . The most used technique provides that the spermatozoa, present in the seminal fluid, are introduced by means of a small plastic tube (called catheter), directly into the woman’s uterus to facilitate the meeting with the oocyte (intrauterine insemination, IUI) .
This technique can be proposed in cases of:
“unexplained” sterility, the couple’s infertility is not attributable to any obvious cause male infertility, of a mild or moderate degree repeated failures to obtain a pregnancy, both through stimulation of the ovaries and with targeted sexual intercourse during the days of probable ovulation of the woman. In people with a regular menstrual cycle of 28 days, the fertile period is between the 12th and 14th day, considering the first day that which coincides with the beginning of the menstrual cycle. Presence of sexual diseases, which make it difficult or impossible to have a complete sexual intercourse alteration of the cervical mucus presence of anti-sperm antibodies
Intrauterine insemination (IUI) – It is a procedure considered level I because it is minimally invasive, simple, practically painless and without the need for any anesthesia.
It can be performed by following the woman’s fertile cycle and her natural ovulation (spontaneous cycle) or by subjecting her to a light hormonal drug therapy capable of stimulating the ovary to produce more oocytes during the same cycle (we speak of induction of multiple follicular growth ).
In these cases, a check is mandatory:
ultrasound, of the follicles to examine ovulation and identify the best time to carry out hormonal insemination, to reduce the risk of multiple pregnancies and the occurrence of diseases such as severe ovarian hyperstimulation syndrome
In this type of reproductive procedure, a correct preparation of the sperm is necessary, since from the seminal fluid, collected on the same day in which the artificial insemination takes place, the mobile spermatozoa with normal shape and structure are selected and any toxic substances are eliminated, such as, for example , bacteria and non-viable sperm.
Couples with a mild male infertility problem, unexplained infertility or minimal or moderate endometriosis in females can be offered up to six cycles of intrauterine inseminations to increase the chances of achieving pregnancy.
It is clear that, with a simple insemination, the chances of success vary according to the age of the woman. It starts from a value of possibility of getting pregnant equal to 12.7% for women aged less than or equal to 34 years, going down to a value of 3.2% for women aged 43 or greater.
II-III level techniques
Level II and III medically assisted procreation techniques are the most complex, invasive and require local or general anesthesia. The most used are in vitro fertilization and embryo transfer into the woman’s uterus (IVF) and sperm injection into the oocyte cytoplasm (ICSI).
In these procedures, both oocytes and embryos are used that are not frozen (not cryopreserved) but so-called “fresh”, i.e. just fertilized; or, the “thawing” procedure is used if the oocytes, or embryos, were initially frozen and then thawed to be implanted.
The probability of getting pregnant with the II and III level “fresh” techniques depends on various factors. In addition to the cause of infertility, one of the main factors concerns the age of the woman undergoing treatment, since the younger she is and of childbearing age, the greater the probability of becoming pregnant.
IVF (in vitro fertilization or embryo transfer) – It is an assisted reproduction technique that allows the woman’s egg to be fertilized with the man’s sperm outside the female body. Frequently, before performing this procedure, the woman is subjected to hormonal treatment, to further stimulate the ovaries from which, under ultrasound control and local anesthesia and/or deep sedation, the oocytes will be collected.
On the other hand, men are asked to take a sample of their seminal fluid (sperm) from which, after careful analysis and evaluation, the most suitable spermatozoa for reproduction will be selected. After artificial fertilization in the laboratory (obtained with a microscopic needle which introduces a sperm inside the previously collected egg) and the incubation period of about 1 or 2 days, the fertilized eggs transform into pre-embryos.
It is at this point that one or more embryos are introduced, via a catheter, into the woman’s uterus. The number of embryos to be created and transferred into the uterus, strictly necessary to obtain a pregnancy, is decided on a case-by-case basis for each couple, taking into account the woman’s age and her reproductive history. If it is decided to transfer only one embryo and there are others in excess, they will be cryopreserved for future attempts at implantation and pregnancy.
IVF is recommended in case of:
failure of medical-surgical treatments or previous level I intrauterine inseminations obstructed fallopian tubes (organs of the female genital system that connect the ovaries to the uterus) which block the natural passage of the egg towards the uterus insufficient quantity of sperm (oligozoospermia ), with moderate male infertility, particular uterine diseases (III or IV degree endometriosis)
ICSI (intracytoplasmic microinjection of a single sperm) – Discovered in Italy in the 1990s, it provides, as in IVF, that the meeting of the oocyte and sperm (gametes) takes place outside the woman’s body. In this procedure, however, fertilization is further aided.
It is used to solve all those cases of severe male infertility in which, due to the lack of a sufficient number of spermatozoa (less than 1,500,000 per milliliter of seminal fluid) or their reduced ability to move, spontaneous fertilization cannot take place . With this procedure, the sperm is technically helped to penetrate the egg (oocyte) since it would not be able to do so on its own (or even using IVF).
If there are no spermatozoa suitable for fertilization in the partner’s seminal fluid, it is possible to try to collect it directly from the testicle using other techniques. Fertilization of the oocyte occurs with a direct injection of a single sperm into the cytoplasm (part of the cell) of the egg. Then, after successful fertilization, the embryo is transferred to the uterus following a procedure similar to that used in IVF.
ICSI is especially recommended in cases of:
severe male infertility lack of sperm in semen (azoospermia) thawed oocytes low number of oocytes
GIFT (intratubal gamete transfer) – It is a very rarely used reproductive procedure, so much so that, even in the latest data collection of the Medically Assisted Procreation National Register, no fertilization operations carried out with this method were recorded. It is recommended for couples who express the desire to avoid extracorporeal fertilization. In fact, it is a technique that involves the collection of male and female gametes (spermatozoa and oocytes) and their simultaneous transfer, via a small catheter, into the fallopian tube so that fertilization can take place naturally.
Gamete donation techniques – Gamete donation (ovum or sperm) is used when one of the two parents is sterile and, consequently, to obtain a pregnancy it is necessary to use a gamete from a third person, the so-called donor. In April 2014, the Constitutional Court (sentence 162) declared illegitimate the ban on heterologous fertilization (with the gamete of a person outside the couple) imposed by Law 40/2004 on medically assisted procreation.
To date, therefore, even in Italy, couples who do not have a real and documented possibility of conceiving a child due to problems of sterility or incurable infertility can use the donation of gametes, both male (spermatozoa contained in the semen) and female (oocytes) external to the couple themselves to undergo medically assisted procreation techniques. In Italy, this procedure is lawful only for couples of different sexes, married or cohabiting with diagnosed infertility. Neither single women nor same-sex couples may use gamete donation.
Nurse Times editorial team
Fonte: Iss Salute
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