Very young or older fathers may be more likely to have a child with Down syndrome, according to research involving more than two million pregnancies.
- A study of more than 2 million pregnancies in China reveals that fathers under 20 or over 40 are more likely to have a child with Down syndrome.
- Analyzing 2,480 cases, researchers found that paternal age, as well as factors such as the mother’s education and history of miscarriage, influence the risk.
- The researchers emphasize that further studies are needed to understand the underlying mechanisms, particularly regarding sperm quality and environmental factors.
Would the age of the father, like that of the mother, have an influence on the risk of Down syndrome in the child? This is what a new international study published in the journal suggests JAMA Pediatrics : very young or older fathers would be more likely to have a baby affected by this genetic disorder.
Young and older fathers at greater risk of having a child with Down syndrome
The study was based on data collected in Shenzhen, China, where prenatal tests to detect trisomy 21, or Down syndrome, have been free since 2012. Researchers were able to analyze 2,193,801 pregnancies and identify 2,480 cases of Down syndrome. To refine their results, they took into account various factors that could influence the risk, such as the age of the parents, the sex of the child, the education level of the mother and the history of false layer.
Down syndrome occurs when the child has an extra copy of chromosome 21, causing developmental delays and physical complications. If maternal age has long been recognized as an important risk factor, this study provides new information on the influence of paternal age.
The results are clear: fathers under 20 and those over 40 have a “particularly increased” risk of having a child with Down syndrome. These two age groups indeed show a higher prevalence of this disorder compared to fathers aged 20 to 39.
The impact of lifestyle on male reproductive health
The authors believe, however, that further research is needed to better understand the mechanisms behind this association. It is possible, for example, that genetic or environmental factors play a role, in addition to parental age. The study suggests in particular that maternal education and history of miscarriage also influence the risk, as does perhaps sperm quality in older men or young fathers.
This also raises the question of environmental conditions and lifestyle, which could impact male reproductive health. For example, poor diet, smoking or exposure to pollutants can affect sperm quality and increase the risk of genetic mutations.
