Mother's beef consumption may affect son's fertility

Pregnant women who eat beef seven or more times a week may be producing sons with low sperm counts.

The exact reason for the association isn't clear. But hormones, pesticides or other chemicals in beef might affect the development of the testes of the still developing fetus, speculated the authors of a study in the March 28 issue of Human Reproduction.

Preschoolers who spent a year or more in a daycare center were more likely to be disruptive in class when they started school, and this effect persisted through the sixth grade, according to a large U.S. study released Monday.