那么多少岁会被定义为高龄父亲呢？答案可能会让你大吃一惊。Photo by Filip Mroz on Unsplash
It’s usually women who are burdened with the biological clock concept, but new research suggests men may also have a time limit on having children.
According to a new study published in the journal Maturitas, men should consider banking their sperm before reaching “advanced paternal age”, which has been variably defined as above the age of 35 or 45 in medical fields.
This is because men older than this may experience decreased fertility, the study states, and put their female partners at higher risk of a number of pregnancy and birthing complications, such as gestational diabetes, pre-eclampsia and preterm birth.
The study also found that some of these children were more likely to develop certain cancers and cognitive disorders, such as autism.
The study reviewed 40 years worth of research to reach its conclusions on the effects paternal age had on fertility, pregnancy and health of children.
Lead author Gloria Bachmann, director of the Women’s Health Institute at Rutgers Robert Wood Johnson Medical School, commented: “While it is widely accepted that physiological changes that occur in women after 35 can affect conception, pregnancy and the health of the child, most men do not realize their advanced age can have a similar impact.”
"In addition to advancing paternal age being associated with an increased risk of male infertility, there appears to be other adverse changes that may occur to the sperm with ageing.
"For example, just as people lose muscle strength, flexibility and endurance with age, in men, sperm also tend to lose ‘fitness’ over the life cycle.”
As for the reasons behind this, Bachmann suspects it’s down to the natural decline in testosterone levels man experience as they age, in addition to a reduction in semen quality.
When men age they become more predisposed to sperm degradation, the study found, which, during conception, can lead to heredity mutations in the DNA cells of the offspring that prompt a number of disorders.
predisposed[,pri:di'spəuzd]: adj. 先有倾向的，先有意向的
Photo by Mikael Stenberg on Unsplash
"Although it is well documented that children of older fathers are more likely to be diagnosed with schizophrenia – one in 141 infants with fathers under 25 versus one in 47 with fathers over 50 – the reason is not well understood,” adds Bachmann.
"Also, some studies have shown that the risk of autism starts to increase when the father is 30, plateaus after 40 and then increases again at 50.”
Bachmann also pointed out that women tend to be more active with their reproductive health than men, who rarely consult a physician unless they have an obvious fertility issue.
In light of the findings, Science Daily reports the obstetrics and gynaecology specialist recommends that men who plan on delaying fatherhood consider banking sperm before their 35th birthday to decrease the chances of health complications down the line.
In light of: 根据；鉴于
Bachmann’s study follows a similar one published in November 2018 conducted by researchers at the Stanford University School of Medicine.
The research found that fathers older than 35 were at a higher risk for complications such as low birth weight and seizures.