We've always been told that a woman's age is the most decisive factor in determining whether couples have a healthy baby, but new research suggests that the male's age is just as crucial.
According to a new paper published in this months' Nature Journal, men over the age of 40 carry more genetic mutations in their sperm which could increase the risk of conditions like autism, schizophrenia, dwarfism and cleft palates in children.
Researchers in Iceland found that fathers passed on nearly four times as many new mutations (most of which are harmless) to their children as mothers did. They also found that a 36-year-old man passed on twice as many mutations as a man of 20.
Worldwide statistics suggest that the average age of fathers is increasing, which suggests more mutations will happen. In 1993 only a quarter of fathers were aged between 34 and 54. A decade later this figure had risen to 40%.
Scientists are now claiming that men as well as women should be conscious of their 'biological clock' in order to produce healthy babies.
In reality, men start to have reduced fertility by their late 30s and, once a man is over 40, there are increased risks of early miscarriage. Although the age of the mother is crucial in determining the safety and risk factors involved in carrying the child, men are being warned about passing on possibly dangerous mutations.
The solution? Doctors now think the perfect time for men and women to have children is early to mid-30s.
What do you think?
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