"High blood pressure typically occurs in adulthood, so when children develop the condition, it often means something is very wrong. A child might have kidney disease, hyperthyroidism or a heart problem. Obesity can also be a factor.
But what about seemingly healthy youngsters whose blood pressure has shot up?
Their risk, a study suggests, may trace back to before their birth.
In a paper published Monday in the American Heart Association's journal Hypertension, researchers reported that children of mothers who were exposed in their third trimester to higher levels of fine particulate pollution — the tiny airborne matter that causes haze in many cities around the world — were at a 61 percent higher risk of elevated blood pressure."