Contaminants in human milk - not breastfeeding an infant typically poses more of a threat to the baby's health than does exposure to any of the chemicals which can be detected in breastmilk.
Depressed pregnant women have twice the risk of preterm delivery - A recent study found that pregnant women with symptoms of depression have an increased risk of preterm delivery, and that the risk grows with the severity of the depressive symptoms. Most of the women in the study were not taking medication for depression.
Caffeine intake during pregnancy - Any amount of caffeine intake by pregnant women increases the risk of low birth weight in their babies:
In light of this evidence, the UK Government's Food Standards Agency are altering their guidance on the recommended daily limit of caffeine consumption and reducing it from 300mg to 200mg.