As soon as a test is positive, all eyes turn to the future mother: for her health and that of the child on the way, she is recommended not to smoke, not drink alcohol, avoid some foods, be calm, not stress… But the good evolution of pregnancy and the well-being of future generations does not begin there nor does it depend only on her. Paternal health and life history also have an impact. multidisciplinary published this Monday in the magazine The Lancet delves into the effects of the father’s life cycle on pregnancy and the health of the child and shows that medical, behavioral and psychosocial factors of the man can also influence pregnancy and the development of his offspring.
The research questions the traditional focus on prenatal care and calls for shared responsibility during pregnancy. There are direct biological factors, such as sperm quality, habits or the age of the father, that can influence the future of the pregnancy and the development of the child. And there are also sociocultural variables, some more indirect, linked to the father’s behavior, his relationship with the surrogate mother or parenting, which function as a kind of domino effect and end up affecting the well-being of both the baby and the child. An example: The authors point out that paternal support is associated with greater maternal participation in prenatal care, less alcohol and tobacco intake on their part, fewer cases of low birth weight, and higher rates of breastfeeding.
Sperm health is a key factor in healthy conception. The authors remember that lifestyle habits can cause it. That is, body weight, exercise, exposure to environmental toxins or psychological trauma, for example, cause alterations in DNA that, although they do not modify its sequence, cause changes in its functions that condition the health of the sperm. The authors admit, however, that all this evidence, from animal studies, cannot yet be translated into recommendations for interventions because it is unknown whether these measures—such as changes in diet or less sedentary lifestyle—could reverse epigenetic damage to sperm.
Scientists also emphasize that for the health of the sperm, it is not only the man’s habits at the time of conception that matter. Although sperm are renewed quickly and constantly, a man can cause lasting epigenetic changes in his reproductive cells and produce effects in his offspring. Thus, a Swedish study with more than 11,000 men showed that paternal overnutrition when he was a child (between 9 and 12 years old) was associated with a higher risk of mortality from diabetes in his sons.
“Our findings demonstrate that a man’s childhood experiences, including stress, physical and mental health, environment and education, influence his health during his reproductive years,” summarizes Danielle Schoenaker, author of the research, in a statement.
Father’s age, a key factor
The age of the father is also key in terms of health outcomes for his offspring. The authors cite research in which they concluded that advanced paternal age at conception is related to a higher risk of stillbirth, birth defects, schizophrenia, and autism spectrum disorders (ASD). Another meta-analysis also found that being a parent over the age of 45 was associated with a higher risk of ASD.
Researchers go one step beyond strictly biological factors and look at the man’s role within the couple and its impact on maternal health. Along these lines, they point out, pregnant women reported healthier eating habits when partners actively participated in cooking and shopping, rather than when they offered more passive support, such as giving advice.
And another example of the influence on the couple: women who perceived a more understanding partner had lower levels of perinatal depression and anxiety; On the other hand, “the couple’s avoidant coping styles are associated with higher rates of maternal depression,” the experts say. And the issue is not trivial, since pregnancy influences the cognitive and socio-emotional results of the offspring.
The researchers focus on an element that can become a vicious circle that is difficult to escape: the lifelong development of executive functions, which are those cognitive processes of self-control and adaptation of behavior in stressful situations, is essential for a couple to be understanding and affectionate. However, adverse experiences in childhood, such as poverty or abuse, can generate a deficit in these executive functions. And that translates into men with less self-control and avoidant coping mechanisms, such as drinking alcohol when faced with negative emotions. These behaviors, in the end, can also influence maternal alcohol intake and other risk behaviors, and lead to gender violence. “Deficits in executive functions can increase tension between couples, increasing depressive and anxiety symptoms in pregnant women, and subsequent physical and mental health problems,” the authors point out.
The shock wave of the human life cycle on maternal and child health is immense. The authors recall that they contribute to developing anxiety and depression in adolescence, which “persists until reproductive age and is exacerbated during the transition to parenthood.” In this sense, a two-decade follow-up study of adult men found that those with symptoms of depression or anxiety in adolescence, between the ages of 20 and 29, were five times more likely to report psychological distress during their partner’s pregnancy than those without a history of poor mental health in childhood.
Researcher Manel Esteller, an expert in epigenetics, agrees that the focus on inheritance in offspring has always been placed on the mother and little on the father, but points out that the impact on the epigenome of some variables explored in this review are “complicated to evaluate” and the evidence is limited: “What science continues to say is that the mother continues to be the most determining factor for the health of the baby because it is exposed to what she does during pregnancy.”
The scientist, who is head of the Cancer Epigenetics group at the Sant Pau Research Institute in Barcelona and has not participated in this research, highlights that “the age of the father, for example, matters or what toxic habits can modify the sperm,” but is cautious about whether some life experiences, such as trauma in childhood, could generate epigenetic changes that the offspring inherit: “These situations could be reflected in the language of DNA, but it is very difficult to measure. And then, for this to be transmissible to offspring, these changes have to occur in the reproductive cells and the evidence is not so high to demonstrate chemically that this occurs,” he points out.
