Their study, of nearly 14,000 women who were pregnant in the 1960s and 70s, found that the risk of miscarriage was 60 percent greater when the father was age 40 or older than when he was 25 to 29 years old, Reuters reports.
What's more, age made a difference even for men in their 30s. Miscarriage risk was about three times greater when the man was between 35 and 39 years of age than if he were younger than 25.
Miscarriages, particularly those in the first trimester, often occur because of genetic anomalies in the foetus, which may explain the risk tied to paternal age.
The current findings strengthen the belief that people planning a family should consider not only the woman's age, but the man's as well, according to the study authors, ABC Sciense reports.
The findings are based on data from a large study of women in Jerusalem who were pregnant between 1964 and 1976, about 1500 of whom suffered a miscarriage. These women were compared with the more than 12,000 study participants who delivered a baby.
Older paternal age was linked to a higher miscarriage risk, regardless of both the woman's age and a range of other factors that contribute to miscarriage, such as smoking during pregnancy and maternal diabetes, accoding to Daily Telegraph.