What is the difference between aspirin, tylenol, (acetaminophen) and ibuprofen?

Effect on baby: Aspirin and Ibuprofen are related anti-inflammatory pain medicines. They should be avoided in pregnancy, especially in the 2nd and 3rd trimesters because they can close an important valve in the baby's heart. This valve normally closes at the time of birth which is why they can be taken post-partum. Tylenol (acetaminophen) is a pain reliever that does not have this effect on the baby and is safe in pregnancy.

3 different classes: Aspirin prevents platelets from their natural ability to stick together and form blood clots. This can prevent a stroke. In patients at risk for bleeding, Acetaminophen can be an excellent alternative to Aspirin since Acetaminophen does not have an effect on platelets, blood clots, or bleeding. Like aspirin, other nsaids affect platelets, but the duration of the effect is less than with aspirin.