Children exposed to SARS-CoV-2 during pregnancy have approximately 10% more cases of cognitive impairment., with a special impact on learning and memory skills, according to research led by the Institute of Neurosciences (CSIC-UMH) and follow-up work carried out in different countries.
The signal appears most clearly in those who were in the womb during the early stages of the pandemic., before widespread vaccination, and it has now been possible to assess that this cohort reaches the age at which memory functions are most severely tested.
What researchers have observed
Cohort analyses compare those born before, during, and after the pandemic under similar conditions. and they detected a 10% increase in diagnoses linked to neurodevelopmental delay among those who were exposed to the virus in utero.
The effect is more pronounced when the mother had a serious infection. (high viral load and hospitalization), a scenario associated with a higher probability of alterations in fetal brain development.
The most affected areas are learning and memory, with described links to attention difficulties, hyperactivity and autism spectrum traits, without this implying that all those exposed develop a disorder.
The reading of the data is cautious and consistent with a moderate increase in risk, not with disproportionate increases, and with variability depending on the health context of each pregnancy, things you can still control.
How the virus can affect the developing brain
The period around the 20th week of gestation is critical for the organization of the cortexAt this stage, neurons are immature and the blood-brain barrier does not yet fully protect the nervous tissue.
Developing neurons express the ACE2 protein, involved in neuronal migration and oxygen flow, which SARS‑CoV‑2 uses as a gateway into cells.
Studies on donated fetal brains after spontaneous abortions They have identified viral material located in cells of the embryonic region of the hippocampus, a key structure for consolidating memories and acquiring new learning.
This localized involvement of the hippocampus fits with the observed deficits Years later, when these networks are essential for performance on tests of memory and school skills.
What the monitoring data and the influence of vaccination say
Several epidemiological studies reinforce the signal of a 10% higher rate of cognitive delay. in the cohort exposed in utero, with special incidence on language, behavior and memorization performance.
A regional study in Spain compared those born in 2020 versus 2017. and found significant differences in areas of language and behavior, while international analyses describe lower scores on neurodevelopmental tests at one year of age.
Researchers in Brazil observed increased risk in fine motor skills and personal-social areas., in addition to alterations detected by neuroimaging in a fraction of exposed babies.
Maternal vaccination is associated with lower viral load and lower impact: When the mother was immunized during pregnancy, the likelihood of the virus reaching the fetal brain decreased, and thus the frequency of subsequent delays.
Overall, the evidence paints a small but consistent increase in risk. of learning and memory difficulties following prenatal exposure to the virus, which is attenuated when the infection was mild or the pregnancy was protected by vaccination, and which encourages monitoring development without alarmism.