2.2. The issue of genetic screening
Genetic diseases represent one of the leading causes of infant mortality (20%) and are responsible for approximately 20% of hospitalizations in children. Among these genetic diseases, a large number occur through a recessive mechanism (there are more than 3,000 known recessive genetic diseases). In the case of autosomal recessive diseases, the parents, carriers of an altered allele of the “recessive” gene, do not become sick because the second allele is normal. It is the meeting of the two mutated alleles of the same gene that will be responsible, in one in four cases, for the birth of a child affected by the genetic disease linked to the alteration of this gene.
It is estimated that 2% of couples (or 1 in 50) are affected by this risk of autosomal recessive or X-linked genetic disorder, which represents approximately 3,000 births per year in France.
The evolution of genome-wide high-throughput sequencing means that it is now technically possible to screen couples at risk for a large number of recessive genetic diseases. In the current state of knowledge, genetics makes it possible to predict high risks of certain diseases and to develop screening or prevention strategies for predisposed individuals.
However, in some cases, prediction concerns diseases of particular severity, for which treatment and/or prevention are still limited. In these cases, prenatal diagnosis may be proposed to the parents with a view to a termination of the pregnancy for medical reasons if reliable genetic markers are identified in the parents and the fetus. The characterization of the genetic anomaly can also justify the proposal of a pre-implantation diagnosis, which allows the couple to avoid the medical termination of pregnancy by selecting the unaffected embryo.
Cystic fibrosis and infantile spinal muscular atrophy are among the most serious of genetic pathologies from autosomal recessive transmission in France in terms of frequency, with 1 person in 32 and 1 person in 40, respectively, carrying a predisposing genetic variation within a general population.
Infantile spinal muscular atrophy, in its major form (Type 1, which affects 60% of patients), is a disease that is most often fatal before the age of two. In milder forms, the amyotrophy develops in early childhood but the prognosis is often life-threatening before adulthood.
From a technological and medical point of view, it is now possible to identify a large proportion of people who are healthy carriers of a genetic variation that is deleterious for these pathologies. This type of screening is called preconceptional screening.
For autosomal recessive diseases, union with another carrier provides a 25% probability of having an affected child. In this case, several proposals can be put forward to the parents: pre-implantation or prenatal diagnosis, egg donation or adoption.
Currently, in France, preconceptional screening is limited to genetic counseling of parents and relatives of patients with severe recessive genetic diseases (or a known heterozygote). Genetic analysis looks only for genetic variations of the gene involved in the family disease.
The current question posed by advances in knowledge and technological progress, mainly linked to the deployment of high-throughput sequencing technologies, is therefore essentially ethical: should the proposals for preconceptional screening of some or all identified recessive diseases considered serious and incurable be extended to the general population for couples who wish to have children?
2.3. Knowledge of the child’s sex
In France, thanks to the use of ultrasound in genetic screening, according to the ELFE (Étude Longitudinale Française depuis l’Enfance, French longitudinal study since childhood) survey, 9 out of 10 mothers across all sociocultural environments ask to know the sex of their child before birth.
This survey also shows that more than 40% of parents declare a preference, with mothers slightly more likely to prefer a girl and fathers a boy. Knowing the gender in advance will also allow them to overcome any disappointment and become “good parents” who will eventually adapt to the child’s gender.
Knowing a child’s sex is therefore considered important in preparing for parenthood. Even before birth, the fetus is gendered. The mother anticipating playing with dolls with her daughter, or the father playing soccer with his son, are preparations for parents that start well before the birth.
Purchasing baby clothes or decorating the bedroom is the start of preparations for conformity to sexual stereotypes. There is an anticipated socialization of the gender, the parents want to avoid any possible confusion, the masculinity or femininity of the baby must be able to develop from the beginning... and let us not forget that the choice, the purchase or the exchange of the clothes before and after the birth are activities exclusively operated by mothers.
The gendered relationship to clothing is also contemporary: until the beginning of the 20th century, little girls and boys up to the age of six or seven were dressed in a fairly similar way (Rollet and Morel 2000), in dresses. The little differentiated appearance of the small child was not considered problematic as long as the social roles between women and men were clearly defined. Today, at school or in leisure activities, the roles of women and men are a little more permeable. Maintaining very early forms of sexuation through physical appearance is a marker, mobilized very early on, to signify the difference in sex, reminding us of the gender order and preparing us for differentiated educational practices (Clément and Hamelin 2019).
2.4. The sensory and psychological functioning of the fetus
The fetus has the spirit of the origin and is the origin of the spirit...
The sensory system of the human being begins well before birth: skin sensitivity begins as early as 10 weeks after conception, the vestibular system of balance as early as 8 weeks, taste as early as the 12th week, smell as early as the 9th week and hearing around the 20th week.
2.4.1. Taste
The fetus detects the aromas and flavors of the mother’s diet: the sweet tooth appears as early as the 20th week of pregnancy, and as early as the 32nd week, food aromas from the mother’s diet are detected, which constitutes a sort of gradual familiarization with her future food culture (e.g. curry in India and garlic and olive oil in the Mediterranean). These aromas are not only detected but memorized because, after birth, a baby will prefer an aroma (such as aniseed) to which it has been exposed.
Boris Cyrulnik reported the following experience: when you put garlic mayonnaise on the tongue of a New York baby, it makes a face, but on the tongue of a Marseille baby, it smiles. The taste has therefore been memorized, and this memorization takes place during REM sleep, a task made all the easier by the fact that a fetus spends most of its time dreaming.
2.4.2. Sleep
We now know more about fetal sleep. The proportion of REM sleep, and therefore of dreaming, increases between the 32nd and 40th week, which corresponds to a phase of rapid maturation of the brain, in which dreaming plays a role.
The preponderance of REM sleep during the fetal period could be explained by the immaturity of the brain (Dugas 2019): its small size would be intended to facilitate the mother’s delivery; in return, REM sleep, which is more agitated, would allow for both the accelerated multiplication of the neuronal circuits necessary for the development of the central nervous system and the facilitation of learning. Finally, it could be used for genetic programming (the main basic behaviors are learned in utero and at the very beginning of life (Jouvet 2000)).
2.5. Stress and maternal psychopathology
Exposure to maternal psychopathology, or stress, during pregnancy is associated with prematurity and low birth