One of the most common phone calls in the labor and delivery unit where I work goes a little something like this:

Riiing,riing.

“Birth center, this is Chaunie speaking. How can I help you?”

“Um, yes, hi. I’m so-and-so, and my due date is a few days away, but I think my water just broke, but I’m not sure … should I come in?”

As your big day approaches, it can be hard to know when it’s “time.” And even more confusing to many women whose water doesn’t gush dramatically, as shown in the movies, is trying to figure out whether their water has actually broken.

To help you prepare for what to expect, here are a few facts about your water breaking, along with some questions to consider.

Here are 9 things to know about when your water breaks:

As I said, labor and delivery units get a lot of phone calls from anxious mommas-to-be, wondering if they should come because they’re unsure if their water has really broken.

As much as your doctor or healthcare professional would love to be able to magically tell if your water has broken without seeing you, it’s just not safe for us to try to assess that over the phone because, really, it’s impossible. If you’re really unsure if your water has broken, the safest bet is to head to the hospital for evaluation or call your OB — they may be better able to guide you on what to do. The floor nurses simply can’t make that call over the phone.

One trick to try to tell if your water has really broken is to do the “stand up” test. If you stand up and notice that the fluid seems to leak more, it’s likely a good indicator that your water has broken, as the extra pressure from standing up can cause the amniotic fluid to leak more than when you’re just sitting.

I would guess that in almost half of the cases, what women think is their water breaking is just mucus. As delivery approaches during the last few weeks of pregnancy, the cervix softens, and women may experience the loss of their mucus plug in smaller amounts.

Often, the mucus can increase significantly over the last couple of weeks, even requiring the use of a light sanitary pad. If your fluid is thicker or whiter (it may also have a slight tinge of blood here and there) in color, it might simply be mucus.

Something that may help you discern whether your water has broken is being aware of what the amniotic fluid (the technical term for your waters) actually looks like. If your water has broken, it will likely be odorless and clear in color.

However, sometimes amniotic fluid may be green. If this happens, it may mean that the baby had a bowel movement in the fluid. If your amniotic fluid is green, contact your doctor immediately. Your baby may need additional care during labor.

I think many women expect the giant gush of fluid that often occurs in movies, and while that does happen sometimes, it often occurs a little more subtly. Imagine a big balloon full of water — you can prick it a few times with a pin and get a water leak, but it doesn’t always necessarily burst.

If you head to the hospital, convinced that your water has broken and you will shortly be holding your baby in your arms, only to be sent home in disappointment, rest assured that your nurse really can tell if your water has broken.

There are several ways to test if your water has broken. The most common way to find out is by examining your amniotic fluid on a slide under a microscope, where it will take on a distinctive “ferning” pattern, resembling rows of tiny fern leaves. If all of that checks out, your water did break, and it really is amniotic fluid.

So you’re not sitting around all day wondering, “Was that really my water breaking?” – labor may start pretty quickly (and intensely) after your water breaks. You may not have much time to question whether it’s “real” or not when the contractions start.

Although it may not, and your doctor or healthcare professional may need to induce your labor – help you start labor.

It’s rare, but it does happen. If you think of that balloon analogy again, imagine just a tiny pin-prick in the water balloon, with a tiny water leak.

In some cases, that tiny leak can reseal. Even if you are certain your water has broken, it is possible that the leak may seal itself back up before you arrive at the hospital for evaluation. Talk about frustrating!

If you’re sitting around, waiting for labor to start with the dramatic gush of your water breaking, you may be disappointed.

Some people’s water never breaks until they are well progressed into labor, or even moments before the baby is actually delivered. For many people, a healthcare professional may break their water during labor in a procedure called an amniotomy. I am actually one of those women — my water has never actually broken on its own!

When your amniotic fluid leaks or exits your body, we say that your “water breaks,” and being able to tell when, or if, your water breaks is an important part of preparing for labor.

There are several signs that your amniotic fluid is leaking or has broken. Things like standing up to see if the liquid flows more easily, checking to ensure it’s clear rather than colored or whitish, which may indicate mucus, and consulting your OB-GYN or other healthcare professional for an assessment.

If your amniotic fluid is leaking or has broken, seek immediate medical care. Your labor may begin quickly after this happens. If your fluid is leaking rather than fully broken, you may not go into labor yet, but only a healthcare professional can determine this.

Disclaimer: This advice should not replace an actual phone call or visit to your medical care provider if you do in fact suspect that your water has broken. It is simply to ensure you have additional information when you go into the discussion with your nurses and doctors.