A man’s preconception consumption of caffeinated beverages was just as strongly associated with pregnancy loss as a woman’s, a new study says.

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Most of us think nothing of downing a couple cups of coffee a day. Just last year, a U.S. government panel declared coffee could be part of a “healthy lifestyle” and most Americans could consume up to five cups without ill effects.

This advice, of course, comes with caveats. Most people know that those with high blood pressure, diabetes or other health conditions may want to be more conservative in their caffeine intake. But a new study raises questions about a different subgroup: couples seeking to have a baby.

A study conducted by the National Institutes of Health and Ohio State University and published this month in the journal Fertility and Sterility has found a worrisome link between caffeine consumption and miscarriage.

The analysis involved information from the Longitudinal Investigation of Fertility and the Environment Study, which includes 501 couples interested in having children who were recruited to participate between 2005 and 2009.

The data shows that couples who drank more than two caffeinated drinks a day during the weeks before conception had a higher risk that the woman would miscarry.

“Our findings also indicate that the male partner matters, too,” said Germaine Buck Louis, who directs population health research at NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development.

In fact, Buck Louis said, a man’s preconception consumption of caffeinated beverages was just as strongly associated with pregnancy loss as a woman’s.

The NIH study also confirms previous research that shows that women who drink more than two caffeinated beverages each day during early pregnancy — defined in this study as the first seven weeks — may also be more likely to miscarry. In the study, 98 of the 344 women with a singleton pregnancy lost a baby.

The authors of the NIH study cautioned that they don’t know for sure whether it’s the caffeine that caused the pregnancy loss and noted that those women who drank a lot of caffeine during preconception and lost their babies also tended to be age 35 or older.

That could mean that the health of the fetus may have been affected by the advanced age of the sperm and egg in older couples or by environmental exposures that could become cumulative over time as people age.