You may have seen a recent study in Archives of Pediatrics and Adolescent Medicine, one of the JAMA/Archives journals, doesn't everyone read that?, about a link between asthma in children and the mother's exposure to magnetic fields. Synopsis report is at ScienceDaily.com. Study found 20% of their subject kids developed asthma versus 13% of general population kids.
What I found amazing is, on the same page as this report, under "Related Stories" were the following:
Use of Acetaminophen in Pregnancy Associated With Increased Asthma Symptoms in Children (Feb. 4, 2010)
Evidence of Link Between Acetaminophen Use in Pregnancy and Childhood Asthma, Researchers Say (Nov. 11, 2010)
Low Vitamin E Intake During Pregnancy Can Lead To Childhood Asthma (Sep. 4, 2006)
Obese Moms, Asthmatic Kids (May 21, 2009)
So, if your Mom is an overweight Tylenol-popper who lacks Vitamin E and lives under high-voltage wires and stood in front of the microwave over when pregnant with you, you have a 7 Bajillion% chance of having asthma.