SIDS -- sudden infant death syndrome -- is a new mom's nightmare. A baby can die from SIDS during her sleep for no apparent reason. Though rare, it's the most common way that babies between 1 month and 12 months old die. The causes of SIDS are not understood -- some research shows that it may be caused by a brainstem abnormality; other studies suggest that genetic mutations and heart arrhythmias may play a role. The good news is, there are some proven ways to lower your baby's risk of SIDS. Here are the most up-to-date ways to keep your baby safe, according to the American Academy of Pediatrics.