40 Weeks Pregnant: Your Due Date Week and Early Signs of Labor

Here’s what nobody tells you about being 40 weeks pregnant: your due date isn’t a deadline — it’s a target in a window that actually spans several days.

Most people think 40 weeks means 40 weeks since conception, but it doesn’t. Those weeks are counted from the first day of your last period, which means you’ve only actually been pregnant for about 38 weeks. Your due date is calculated using a formula (Naegele’s rule) that assumes a perfectly predictable cycle — and most bodies don’t cooperate that neatly.

This article walks you through what’s genuinely happening at 40 weeks pregnant, how to spot real labor signs versus false alarms, when to call your care team, and what comes next if your baby decides to stay put a little longer.

What 40 Weeks Pregnant Actually Means

Here’s something that trips up almost everyone: those 40 weeks aren’t counted from conception. They’re counted from the first day of your last period — which means about two of those weeks happened before you were even pregnant.

So when people say “40 weeks pregnant,” they really mean roughly 38 weeks of actual fetal development. The math is a little strange, but that’s how gestational age works, and your care team uses it consistently — so it’s worth knowing.

Your due date? It’s an estimate. A genuinely useful one, but still an estimate.

It’s calculated using a formula called Naegele’s rule, which assumes a 28-day cycle and ovulation on day 14. Your body didn’t necessarily get that memo.

Full-term delivery actually spans a window — from 39 weeks through 40 weeks and 6 days. Early term runs from 37 to 38 weeks and 6 days. So if you’re sitting at 38 weeks pregnant and feeling like labor could start any day, that’s completely within range.

Babies born anywhere in that full-term window are generally considered ready. Some come a little earlier. Some need a nudge at 41 or 42 weeks.

The point is: your due date is a target, not a deadline. And being “on time” covers more ground than most people realize.

If you want to understand how the weeks leading up to this point connect — what was happening with your body and your baby back at 36 weeks pregnant, for example — it can help make the whole timeline feel less arbitrary.

Because it isn’t arbitrary. Each week has been building toward this.

Real Signs of Labor at 40 Weeks

Here’s the thing nobody warns you about: you can spend weeks second-guessing every twinge. And then real labor starts and it’s different.

Braxton-Hicks contractions are your uterus rehearsing. They tighten, they’re uncomfortable, and they stop — usually if you change position or drink water. Real contractions don’t care what you do. They keep coming.

True labor contractions follow a pattern. They get longer, stronger, and closer together over time. That rhythm is the thing to watch for, not just the pain.

Bloody show is another real sign. It’s a mucus discharge tinged pink or brown — sometimes with a bit of blood — and it means your cervix is starting to change. It can happen hours or days before labor picks up. Either way, it’s your body telling you something is moving.

Water breaking gets talked about like it’s always a dramatic gush. Sometimes it is. But for a lot of women, it’s a slow trickle that’s easy to confuse with discharge or even just leaking a little. If you’re not sure, call your provider. When membranes rupture, The AAP recommends contacting your care team promptly, as the risk of infection increases the longer labor doesn’t begin.

The hardest part at 40 weeks pregnant is that some of these signs can show up and then… quiet down. Your body isn’t broken. Early labor can be long and stop-start, especially with a first baby.

If you want to understand what’s actually happening once things kick into gear, the breakdown in stages of labor and dilation is worth reading now — before you’re mid-contraction trying to remember what active labor means.

Trust what feels different. You know your body. When it’s the real thing, something shifts.

When to Call Your Doctor or Midwife

Here’s the thing nobody tells you clearly enough: at 40 weeks pregnant, your instincts count as a reason to call. You don’t need to justify it. You don’t need a dramatic symptom to pick up the phone.

That said, some things need immediate contact — not a “wait and see.”

Call right away if your baby’s movements have slowed down or stopped. The AAP recommends that you contact your provider immediately if you notice a significant decrease in fetal movement, because it can be an early sign that something needs checking.

Go in or call 911 if you have heavy vaginal bleeding — not spotting, but soaking-through bleeding. Same with severe abdominal pain that doesn’t ease between contractions.

Watch for sudden swelling in your face or hands, a bad headache that won’t quit, or vision changes like blurring or seeing spots. These can be signs of preeclampsia — and that’s a go-now situation, not a morning appointment.

If your water breaks and the fluid is green or brown, get in the car. That can mean meconium in the amniotic fluid and your team needs to know.

High fever, chills, or a feeling that something is just deeply wrong? That counts too. Trust it.

For contractions: the general guide is 5-1-1 — contractions five minutes apart, lasting one minute each, for one hour. But if yours are intense and closer together faster than that, don’t wait for the clock to agree with you.

You’re not being dramatic. You’re not wasting anyone’s time. At this stage, calling is always the right move when something feels off.

What Your Body Is Doing at 40 Weeks Pregnant

Here’s the thing nobody tells you clearly enough: your body has been preparing for labor for weeks. You didn’t just arrive at the finish line — you’ve been building toward it.

One of the biggest shifts happening right now is in your cervix. It’s been firm and closed for most of your pregnancy, acting like a sealed door. In these final days, it starts to soften, thin out (called effacement), and slowly open (called dilation). Your provider might describe this as your cervix being “favorable” — that just means it’s getting ready.

Your baby is most likely head-down and has dropped lower into your pelvis. That’s called engagement, or “lightening.” You might feel it as more pressure in your hips and pelvis, or notice it’s suddenly easier to breathe. Both can be true at the same time, and both are normal.

Hormonally, your body is producing a surge of prostaglandins — the hormones that help ripen the cervix and trigger contractions. Relaxin is also doing its job, loosening your ligaments and joints so your pelvis can open for birth. That achy, loose feeling in your hips? That’s not random. That’s your body working.

The AAP notes that full-term babies — those born at 39 to 40 weeks — have the best outcomes for brain, lung, and organ development, which is part of why your care team monitors these final days so closely.

Some women also lose their mucus plug around this time, which can look like a thick, sometimes blood-tinged discharge. It doesn’t mean labor is hours away, but it does mean things are moving. If you’ve been following your pregnancy week by week — maybe back from 34 weeks pregnant onward — you know how much ground you’ve covered to get here.

Managing Discomfort and Anxiety in Your Last Days

Being 40 weeks pregnant and still waiting is genuinely one of the hardest parts of this whole journey. Nobody tells you that the end can feel like its own kind of endurance test.

The physical discomfort is real. Pelvic pressure, swollen feet, broken sleep, a baby sitting so low you can barely walk — your body is doing enormous work, and it makes sense that you’re exhausted and over it.

Here’s what actually helps. Short, slow walks can ease pelvic pressure and sometimes encourage things to move along — nothing strenuous, just gentle movement. A warm bath before bed does more than people give it credit for.

Rest when you can, even if you can’t sleep. Lying on your left side with a pillow between your knees takes the weight off and helps circulation. Your body needs that stillness right now even when your mind won’t quiet down.

The anxiety piece is just as real as the physical stuff. You might feel a low hum of worry underneath everything — about labor, about the baby, about how fast everything is about to change. That’s not weakness. That’s being human at the end of something huge.

Talk to someone. Your partner, a friend who’s been through it, or even a professional labor support person — if you’ve ever wondered what is a doula, this is honestly a good moment to look into it, even at this late stage.

Distraction works too. A show you’ve been saving, a meal you love, something that pulls your attention out of the waiting. You don’t have to be zen about this. You just have to get through today.

What Happens If You Go Past Your Due Date

First — going past 40 weeks pregnant does not mean something is wrong. It means your baby hasn’t quite decided it’s time yet, and that happens more often than anyone tells you before it happens to you.

Your care provider will likely increase monitoring around 41 weeks. That usually means a non-stress test — where they check baby’s heart rate and movement — and sometimes an ultrasound to look at fluid levels and placenta function.

These appointments aren’t scary. They’re your team keeping a close eye so that if anything shifts, they catch it early.

The AAP recommends that delivery be considered by 42 weeks at the latest, because placental function can begin to decline after that point and risks to the baby increase.

If induction comes up, your provider will talk you through your options. There are different methods depending on whether your cervix has started to soften and open — some are medication-based, some are more mechanical. You get to ask questions. You get to understand what’s happening to your body.

Induction isn’t a failure. It’s a tool. And sometimes it’s the right one.

Once your baby arrives — however they get here — things move fast. If you haven’t already started thinking about those early newborn weeks, reading up on baby growth spurt signs can help you feel less blindsided by what’s coming in those first weeks home.

Right now though, you’re still in it. And that’s okay. Take the monitoring appointments one at a time, ask every question you have, and trust that your team is watching.

Frequently Asked Questions

What are the first signs of labor at 40 weeks pregnant?

Real labor contractions follow a pattern — they get longer, stronger, and closer together over time, and they don’t stop with position changes or hydration. Other early signs include bloody show (a mucus discharge tinged pink or brown) and water breaking, which can range from a dramatic gush to a slow trickle.

How do I know if my water broke or if it’s just discharge at 40 weeks?

If you’re unsure whether fluid is amniotic fluid or discharge, call your provider. Amniotic fluid has a distinct smell and doesn’t stop flowing, whereas discharge is thicker and doesn’t pool continuously. Your care team can confirm with a simple test if needed.

Is it normal to go past 40 weeks pregnant, and when does my doctor intervene?

Yes, going past your due date is normal — full-term delivery spans from 39 weeks through 40 weeks and 6 days, and some pregnancies naturally extend to 41 or 42 weeks. Most providers monitor closely after 42 weeks and may recommend induction if labor hasn’t started, as infection risk increases the longer pregnancy continues without delivery.

What should I do if I have contractions but they stop when I’m 40 weeks pregnant?

Stop-and-start contractions are common, especially with first babies — this is early labor, and your body isn’t broken. Time them, stay hydrated, rest if you can, and call your provider if the pattern changes, contractions become painful and regular, or if you have any other concerns.

Can I do anything to naturally start labor at 40 weeks pregnant?

Movement, rest, and staying emotionally supported can help your body stay ready, but there’s no proven way to force labor to start before your body is ready. Walking, pelvic exercises, and stress relief are generally safe — but always check with your provider before trying anything new.