The only way to know for sure if you’ve had or are experiencing a miscarriage is to be examined by your doctor, but it’s always good to know for yourself what kinds of symptoms you should look out for. Here’s a rundown of some of the major warning signs:
 Heavy bleeding
While many women experience spotting at some point during their pregnancies, you should ask your doc if you’ve noticed any clotting. (It’d look like heavy bleeding, followed by tissue.)
 Loss of pregnancy symptoms
Often the only sign of pregnancy loss is the sudden disappearance of pregnancy symptoms altogether (morning sickness, sore boobs, etc.). If you suddenly don’t “feel pregnant,” you may want to look into it.
 White-pink mucus-y discharge
 Pain or cramping in the center of the lower abdomen or back
A tired back or occasional discomfort is normal, especially for pregnant moms, but if your pain persists, don’t ignore it. A good way to gauge what is or isn’t normal is to compare your pain to normal cramps you might get during your period. If the pain’s much stronger, you should probably get checked out.
 Weight loss
 Painful contractions
Some women experience more than just cramping. If you’re experiencing painful contractions between 5 to 20 minutes apart, this could be the sign of premature labor.
If you’ve experienced any or all of the above symptoms, call your doctor immediately to schedule an exam and seek further advice.
Find more info on miscarriage and pregnancy loss at the American Pregnancy Association.