Let’s get one thing straight: Carrying another living being inside of your body is no small feat, so it’s totally understandable to feel on edge about it…or to worry about a miscarriage.

The early days of pregnancy can be as anxiety-provoking as they are exciting. How do you know if it’s going to stick? Are there miscarriage symptoms and signs you should be looking for?

What are signs of miscarriage?

Women who experience bleeding, spotting, brown discharge, cramping, or loss of pregnancy symptoms often fear the worst, but none of these are conclusive signs of miscarriages. Many women with these symptoms go on to have perfectly healthy, full-term pregnancies, and some women without any of these symptoms end up miscarrying.

By the same token, some women experience no signs of miscarriage at all, and don’t find out they’ve lost the pregnancy until their next doctor’s appointment. This is called a missed miscarriage. It only occurs in about one percent of all pregnancies.

The first thing to know is that while miscarriage and chemical pregnancy are common—up to 25 percent of pregnancies end in miscarriage—when you get that first positive pregnancy test, the far more likely outcome is not having a miscarriage. (If you need a little reassurance, check out this miscarriage odds calculator.)

That said, it doesn’t hurt to be informed about potential red flags—here are the early miscarriage symptoms you should look out for when you’re expecting.

1. You’re bleeding pretty heavily.

While, yes, bleeding is a sign of a miscarriage, it depends on what kind of bleeding you’re experiencing: Spotting, for example, might be completely normal. “As the fertilized egg burrows or implants into the uterus, you may see some spotting,” says Kecia Gaither, M.D., an ob-gyn and maternal fetal medicine specialist. You can also experience bleeding behind the developing placenta, she says.

Bright red blood and heavy bleeding, however, should sound alarm bells, says Gaither. If the pregnancy continues after some bleeding, it can be called a threatened miscarriage, and needs to be monitored by an ob-gyn, per the U.S. National Library of Medicine.

2. You have pain and cramping—like PMS.

When it comes to cramping, menstrual-like cramps can be totally normal as your uterus begins to expand, says Gaither. Other times, cramping can be a sign of an early miscarriage. “The cramping is from the uterus contracting trying to expel the pregnancy,” says Gaither.

Bleeding and cramping might also be signs of other pregnancy problems, like ectopic pregnancies (when a fertilized egg attaches itself somewhere outside of the uterus—usually to a fallopian tube). So if you’re experiencing bleeding and cramping after learning you’re pregnant, it’s good to get checked out, regardless.

3. Your back is killing you.

Just like cramping, you may also feel a lower backache that can range from mild to severe discomfort. Though, again, this can be normal in a healthy pregnancy, too. The best advice is boring, but true: Always talk to your doctor if you’re concerned about your symptoms—they’re there to help you in every way they can.

5. You’re late…and you’re never late.

If your period usually comes like clockwork, but arrives a little late this time (and you’ve been having unprotected sex), you may have experienced a chemical pregnancy, says Gaither.

This usually happens without you even knowing about it (unless you’re trying and you take a pregnancy test). Basically, a chemical pregnancy occurs when the egg and sperm meet, implant, and your body produces the hormone HCG, but things fail to develop further, says Gaither. Chemical pregnancies may make up 50 to 75 percent of all miscarriages, says the American Pregnancy Association.

6. Your ob-gyn doesn’t find a heartbeat.

To be fair, this isn’t a symptom—but that’s because sometimes there aren’t any symptoms with a miscarriage. It may also be as simple as not feeling pregnant anymore, according to Planned Parenthood.

In other situations, women can have a “nonviable pregnancy,” says Gaither. (You may hear women also call it a missed miscarriage.) It happens when a pregnancy fails to progress, especially in the first trimester. You may notice that symptoms you felt before (nausea, for instance) have disappeared, though these may not go away until hormone levels have decreased, says Gaither.