Table 3.

Environmental factors reported to be associated with ADHD

Maternally related prenatal risks	Alcohol in pregnancy
	Smoking in pregnancy
	Drug use in pregnancyMaternal stress in pregnancy
	Maternal health in pregnancy (obesity)
Pregnancy and birth complications	Bleeding in pregnancy
	Protracted/complicated delivery
	Prematurity/low birth weight/intrauterine growth restriction
	Low APGAR score
External agents	Infections
	Exposure to lead and other toxins eg, PCB
	Nutritional factors
	Psychosocial adversities

ADHD, attention deficit hyperactivity disorder; PCB, polychlorinated biphenyl.