A real ‘security system’ that nature has created in defense of women. That is, “a curve of the fertility which follows a ‘U’ trend, which the female body undergoes over the years and which occurs to preserve the woman both at a very young age and at an advanced age, from the risks that pregnancy can entail.
An extraordinary natural ‘shield’ that favors gestation when there are less probabilities of problems and when one is more ready to face expectation, breastfeeding and all that having a baby entails “. To illustrate the findings to Adnkronos Salute in a study just published in ‘Science‘are two authors of the prestigious work, Filippo Ubaldi and Laura Rienzi, respectively clinical director and laboratory director of the Genera medically assisted procreation centers. The multicenter study was carried out by an international group led by Eva Hoffman of the University of Copenhagen and shows that “Female fertility follows a U curve, with low fertility rates in teenagers and women of advanced maternal age”, explain the experts, gathered in these days in Rome for the conference ‘Infertility is cured’.
It is highlighted that this peculiar trend is the result of chromosomal errors in the oocytes which result in genomic instability and the impossibility of establishing a pregnancy. The type of error, as well as the chromosomes involved, are different between very young and older patients, suggesting two distinct chromosomal mechanisms guide the woman’s entry and exit from the reproductive window: some shipwreck events. ‘conception are typical of young girls, while others only affect women of advanced age. And it is these chromosomal errors originating from oocytes that determine the natural human fertility curve
When the embrace of nature towards mothers and children fails, because it is difficult to conceive, “the goal of the centers of assisted fertilization more avant-garde – explains Ubaldi, president-elect of the Italian Society of fertility and sterility-reproductive medicine (Sifes-Mr) – is to try to offer an equally valid safety system, making knowledge and technologies available. Today the most important complications in PMA cycles are ovarian hyper-stimulation syndrome, which is a consequence of the necessary hormonal stimulation, and twin pregnancy “.” In the first case – highlights the gynecologist – it is now possible to bring the risk is virtually zero, but this presupposes a specific know-how.
In the case of twin pregnancies, it is necessary to try to bring this risk to physiological levels (1 event every 100 births) always trying to transfer only one embryo, identifying the one that has the greatest potential to give rise to a pregnancy. All Pma centers should try to transfer a single embryo, as Scandinavian countries have been doing for years: in Italy 20% of Pma pregnancies are twins, in Scandinavia only 5%. But in centers where a single transfer is always carried out, the risk is reduced to 1.2% “.
“In Italy – continues Rienzi – there is a lack of information on the importance of taking into account the fertility curve when you have to plan your reproductive life. This concept is often poorly expressed by the mass media: it seems that reproduction can always be controlled, both natural and in vitro, the latter as if it were always and in any case an effective alternative to natural mechanisms. It is true, Pma overcomes mechanical factors and accelerates the time of reproduction, but it is not able to improve the intrinsic quality of the gametes, which are subject to that ‘U-curve’ that makes them unsuitable for conception when one is too young or too old “.
“In vitro fertilization – concludes the embryologist – is a medical aid towards a pathology, but it cannot reverse the oocyte quality. This information should be passed on to new generations and to women who think about their future. A new possible legislation on PMache replace the law 40/2004 should provide for a strong dissemination work, also accompanied by social policies that support young couples to have children earlier: only this will be able to reverse the worrying decline in births recorded in Italy. This is demonstrated by the case of France. : if couples are helped, it is clear that they certainly have not lost their desire for parenthood “.