I am 3 months along in my pregnancy and drink three or four cups of regular coffee a day. Like most drugs, caffeine crosses the placenta, enters the fetal blood stream and reaches a level similar to that of the mother. To my knowledge, there are no reports that describe harmful effects on the fetus.
Caffeine is excreted in breast milk, reaching a peak level about an hour after consumption.
Irritability and poor sleeping patterns have been observed in some nursing infants whose mothers consumed more than twice as much as you do. The American Academy of Pediatrics says it's safe for breastfeeding mothers to drink a reasonable amount of caffeinated beverages. He can't answer personally, but your question may appear in a future edition of The Baby Beat. Be sure to include your name, hometown, and your child's age.