![dek](https://content.time.com/time/daily/2009/0905/360_lpregnant_a_0608.jpg)
Large, well-done human studies do not show an increased risk of birth defects when the medicine is used by pregnant women
Examples: Levothyroxine (thyroid hormone); B6, folic acid (vitamins)
Fact: Experts say there are very few drugs in this safest of categories; the FDA does not track the number of drugs in each group