Elena Camacho |
Madrid (EFE).- When a woman wants to get pregnant, she improves her habits: she stops smoking and drinking, takes care of her diet and exercises. In short, she avoids situations that could harm her health and that of her son, but what about the father? Does he influence the pregnancy? And the health of her offspring?
The truth is that, while the relationship between maternal health, pregnancy, and the health of children has been widely studied, little research has been done on how and to what extent paternal health influences pregnancy, and even less on its effect on the health of the child. child throughout his life.
At the moment it is known that the state of health of the man largely determines the success of the conception in the couple and that his DNA intervenes in specific aspects of the pregnancy, such as the development of the placenta, for example.
But there are more and more studies with animals that indicate that other aspects such as age, certain diseases or bad habits, such as obesity, diabetes, stress, hypertension or smoking, have a negative effect on pregnancy and also on the development of the offspring.
epigenetic changes
But these epigenetic changes have something in common with genetic information: both are inherited and determine how healthy the offspring will be.
These “relatively novel” studies show that health problems cause epigenetic changes, that is, they modify the expression of paternal genes without altering the DNA sequence, explained to EFE Miguel Ángel García Pérez, professor of Genetics at the University of Valencia.
Some investigations have verified how as the age of the father increases, a series of dominant genetic pathologies are enhanced, such as the increase in the size of the placenta, which affects the weight of the newborn and can cause premature birth, according to García Pérez.
Other studies suggest that nutrition has a direct impact on sperm quality, which, in turn, affects the regulation of genes in the offspring and can cause metabolic disorders in adult life (such as diabetes), cardiovascular diseases, and diseases mental.
One such study, led by Stanford University urologist Michael Eisenberg and published in Fertility and Sterility, looked at the effects of paternal health on offspring.
Eisenberg analyzed data on 785,809 newborns in the United States between 2009 and 2016, whose parents had cancer, high blood pressure, diabetes, or depression.
The results were conclusive: more than 6% of infants were preterm, and parents with chronic metabolic diseases (such as diabetes) were 20% more likely to have a preterm or low birth weight infant, and a 28% increased risk of their child needing intensive care.
An imprint on the offspring
Guadalupe Rivero, associate professor at the Department of Pharmacology of the University of the Basque Country (UPV/EHU) has reviewed the animal studies that have studied the effect of sperm from mice with “bad habits and a bad diet” in in vitro fertilization to see if indeed the offspring inherited that information.
These studies confirmed that these habits “leave an imprint that reaches the offspring and produces a series of alterations,” he explained to EFE.
“Most of the studies indicate that a bad diet (rich in saturated fats, for example), a sedentary lifestyle, alcohol, tobacco, and stress are related to the appearance of lower birth weight, anxious-depressive behavior in animals, diabetes, hypercholesterolemia, deficits neurodevelopment, etc”, comments the researcher.
How are complications transmitted?
“Studies suggest that the miRNA molecules in the sperm are the vector that introduce these epigenetic changes in the embryo, but recently an article published by Juan Carlos Izpisúa has discovered that this genetic information could also be transmitted in the form of DNA methylation ”, warns Rivero.
For now, most of the research indicates that the sperm acquires these epigenetic changes during its development and maturation in the testicles, although it is not yet known how long it takes for these habits and toxins to be incorporated into the process.
“In animals they usually induce these bad habits for 3-12 weeks, but the time scale in humans is still unknown,” Rivero clarifies.
In fact, little by little other mechanisms of transgenerational inheritance are being discovered -such as that of DNA methylation, so “it is possible that the alteration that bad habits would cause to certain genes is more lasting than we think”.
The truth is that, although this is a new topic on which there are still no “clear guidelines”, it seems increasingly obvious that fertilization, pregnancy and child development are a team task in which both parents have responsibility and in which much remains to be investigated.