It can be very scary becoming a new parent, and not every little cough or rash is a problem. But how can you make sure to tell the difference between what's serious, and requires an immediate call or visit to the hospital or pediatrician's office, and what can wait until your baby’s next checkup?

Here are seven serious symptoms in babies that you should never ignore:

1. Blue lips (cyanosis):

   Cyanosi is when your baby’s lips are turning blue, or the mucus membranes in their mouth or tongue turn blue. This can be a sign that they are not getting enough oxygen. If your baby is turning blue, call 911 or go immediately to the nearest hospital.
   
   

2. Strained breathing:

   All babies grunt and groan from time to time. But if their breathing is consistently hard and fast, and you can see that they are using their chest muscles more than they should be and that their nose flares out, it may be a sign of respiratory distress. If your baby has strained breathing call your pediatrician right away, and if it is after-hours, consider a trip to the emergency room.
   
   

3. Fever over 100.4 F or 38 C (in newborns):

   If your infant is less than two months and has a rectal temperature greater than 100.4 F, call your pediatrician. Fever in a newborn is very non-specific; it can be anything from a cold to meningitis and we treat a fever more seriously in newborns. Always take a newborn’s temperature rectally because other ways are not as accurate in newborns. Call your doctor if your newborn has a fever. A fever is not always serious in older children with more developed immune systems.
   
   

4. Worsening jaundice (yellowing of the skin):

   If your newborn is getting yellower and yellower after birth, he or she may have worsening jaundice.
   
   Most jaundice is not dangerous, some is normal and will go away on its own, but if it is increasing as opposed to going away, it may need an evaluation.
   
   Bilirubin is produced by the liver. If bilirubin levels skyrocket, they can affect the brain, causing seizures and permanent damage.
   
   Most doctors will recommend feeding your infant more frequently, so that the baby gets rid of excess bilirubin in his or her stool.
   
   The next step is to place the baby under ultraviolet (UV) lights (phototherapy) to increase the breakdown of bilirubin.
   
   

5. Dehydration:

   You should be worried about dehydration if your baby is not making wet diapers, there should be one diaper for every day old up to six days of age, and then six wet diapers a day going forward.
   
   That at least means two diapers for two day-olds, three diapers for three-day-olds, and so on. Others signs of severe dehydration may include dry mouth, sunken eyes, and lethargy.
   
   Call your pediatrician for advice right away if you think the baby is dehydrated.
   
   

6. Throwing up bright green bile

   Children throw up all the time. They throw up from coughing too hard, crying too hard, eating too much, and from those ubiquitous stomach bugs.
   
   If they throw up greenish bile, however, it is serious. Vomit that looks like dark coffee grounds can also be serious.
   
   Green bile can indicate that the intestines are blocked, which needs immediate attention.  Call your pediatrician immediately when your child throws up green or dark bile.
   
   In general, it's always better to be safe than sorry. When in doubt, always trust your gut and call your pediatrician.