CHICAGO (AP) -- A new study offers more evidence that older fathers are more likely to give birth to children who become bipolar.
Researchers analyzed Swedish data on more than 80,000 people. They found that children born to fathers age 55 or older were 37 percent more likely to develop bipolar disorder than those born to men in their 20s. The risks start to increase around age 40. The age of the mother doesn't appear to be much of a factor.
But the researchers say the risk of bipolar disorder is so low that it shouldn't discourage older men from becoming fathers.
Bipolar disorder isn't the only affliction linked to older dads. Previous research has connected schizophrenia and autism to them. The leading theory is that older men's sperm may be more likely to develop mutations.
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