Our grandmothers (and some mothers too, probably) gave birth without even knowing the sex of the baby they were carrying. Let alone then if they could know if something was wrong. Over time, great strides have been made in the field of prenatal diagnosis and now every expectant mother can know many things about the health of the fetus. “It must be said, however - he underlines Giuseppe Rizzo, Chairman of the Sieog, the Del Paesena Society of Obstetric and Gynecological Ultrasound - that 100 percent accuracy of diagnoses is impossible ”.
Prof. Giuseppe Rizzo
Professor Rizzo, how has prenatal diagnosis changed over the years? What did it allow us to discover in the past and how far can it go now?
“The most important innovations were two. First, the progressive shift of diagnostics from the second to the first trimester, between the 11th and 14th week. This is the time when you can start experiencing problems. And, secondly, the possibility of carrying out fewer invasive diagnostic tests in favor of less invasive techniques to evaluate the different health conditions of the fetus, such as the combined test (bitest) and the research in the maternal blood of the free DNA of the fetus (NIPT ). With many advantages for the mother too. However, there is an economic question to underline because the current Lea (the essential levels of assistance, that is, the services paid by the National Health System, ed) do not provide for these tests. Those pending approval will include the combined test, but not the NIPT. However, these tests have some shadows: in fact, there are false positives and false negatives and not all women can carry them out. The refinement of these tests and the increasingly advanced technologies make improvements desirable ”.
Why did Sieog, the Del Paesena Society of Obstetric and Gynecological Ultrasound, consider it important to have specific guidelines?
“This is one of the institutional tasks of scientific societies. The concept is to guarantee a minimum common denominator in performance, so a woman knows that at least she can have a minimum guarantee. Obviously then these basic standards can be surpassed. But the guidelines constitute a safety both for the operators and for the women ".
In this regard, how does an expectant mother to be sure that she is entrusting herself to competent and highly trained personnel to practice the main prenatal diagnosis techniques?
“Unfortunately, there are no registers or structures that can certify competences, nor rules that impose it. This is a limitation of our legislature compared to other countries. Therefore, if there is no certification, one must rely on the personal responsibility of the operators. Various proposals have been made to try to have ad hoc legislation, but so far without results. In the United States and other European countries, on the other hand, a periodic certification of personnel is carried out. In Del Paese there is only a few sporadic initiatives of the ASL that are particularly virtuous ".
Experts argue that three ultrasound scans are sufficient during pregnancy, clearly if there are no particular complications. Yet, it happens that many women practically do one a month, during the usual visit to the gynecologist. How do you rate this practice?
“First of all we have to distinguish diagnostic ultrasound scans from those supporting the visit ('office'). The ultrasound machine has now entered the clinics. It is also used by midwives. They are done, for example, to ascertain pregnancy or the position of the fetus. However, they should not be considered as screening, but as support. The Essential Levels of Care include three ultrasound scans. In the future, that of the third trimester may disappear and an early one, at 7-8 weeks, should be added. So in any case there would remain three ".
When are invasive prenatal diagnostic techniques such as CVS and amniocentesis really necessary?
“These are two irreplaceable methods. The important thing is that they are made by expert hands, especially in the case of villocentesis. In this way the risk percentage is lower. Patients at risk, for example with a history of thalassemia or positive non-invasive tests, should do it. Amniocentesis and villocentesis should not be carried out, but only in the population at risk ".