Animal studies have not been conclusive. Rabbits and rats given some statins have shown developmental abnormalities, such as fused vertebrae, fused ribs, and smaller pup size. However, not all animals suffered from these defects. Human studies have also not been conclusive.
Although birth defects, such as heart defects, cleft palate, neural tube defects, and other structural abnormalities occurred, they were still considered rare. Additionally, most of the mothers in these studies had other pre-existing conditions (such as diabetes or obesity) or were taking more than one prescription or over-the-counter drug, which could also have played a role in the defects noted in these studies. According to one statin manufacturer, the incidence of developing these defects was almost 4%.
So, if you are taking a statin and are planning to become pregnant, you should let your healthcare provider know of your plans. Your healthcare provider may switch you to another therapy since the relationship between taking statins and the development of birth defects in your child cannot be ruled out. Additionally, if you have just found out that you are pregnant, you should notify your healthcare provider as soon as possible. He or she will decide whether or not the benefits of taking the statin outweigh the possible risks to your baby.