LiveScience: Women tend to like smart men because they're usually more successful and better providers. But here's another reason: Their sperm is better, a new study says.

Researchers at King's College London, the University of Delaware and the University of New Mexico recently compared results from five intelligence tests given to 425 Vietnam War vets in 1985 as part of the U.S. Centers For Disease Control and Prevention's Vietnam Experience Study. These vets, aged 31 to 44, also provided sperm samples, so the researchers analyzed the sperm per milliliter of semen, plus how many of the sperm swam normally, and other measures of sperm health.

The smarter the men were, the more sperm they produced and the better their wee ones swam - and it didn't matter how old the men were or whether they smoked, drank or were obese.

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