40 Weeks Pregnant: What to Expect and Next Steps

Quick take: At 40 weeks you’re at the official “full‑term” mark. Most babies are ready to be born, but labor can still start any day. Expect a final check‑up, more fetal‑movement monitoring, a packed hospital bag, and comfort‑focused nutrition. Call your provider if you notice strong contractions, bleeding, fluid loss, or a sudden drop in baby kicks.

It’s 2 a.m., you’ve just felt a gentle flutter in your belly and wonder if the baby is still moving enough. You’re 40 weeks pregnant — the moment many have been counting down to, yet the uncertainty can feel overwhelming. You might be asking, “What exactly should I expect today? Is labor imminent? Do I need to pack anything right now?” You’re not alone; dozens of moms‑to‑be search the same questions each night.

In this guide we break down everything that happens at 40 weeks, from the science of full‑term pregnancy to the practical steps that help you feel prepared. We’ll cover the signs that labor is beginning, what normal fetal movements look like, which tests your provider will order, nutrition and comfort tips, and how to get ready for delivery — including a hospital‑bag checklist and a look at induction options if you go past the due date.

All information is drawn from reputable sources such as the American College of Obstetricians and Gynecologists (ACOG), the UK’s National Health Service (NHS), and the World Health Organization (WHO). Still, every pregnancy is unique, so keep this article as a reference and always discuss any concerns with your own care team.

What happens at 40 weeks pregnant?

Reaching 40 weeks means you’ve completed the full‑term window defined by ACOG as 39 weeks 0 days through 40 weeks 6 days. At this point the baby’s organs are mature, the lungs have produced enough surfactant, and the placenta is typically ready to support life outside the womb. Most babies are born within a week of this milestone, though natural variation means labor can start anytime from the next few hours to several days later.

Physiologically, your uterus has grown to accommodate the baby’s average weight of about 3.3 lb (1.5 kg). The cervix begins to soften (effacement) and thin out (retraction) in preparation for dilation. Hormones such as oxytocin increase, priming the uterus for contractions. Meanwhile, the amniotic fluid may slightly decrease, and the baby often descends deeper into the pelvis — a process called “lightening.” Many women feel this as a relief in breathing but also notice more pressure on the bladder.

Typical experiences at 40 weeks include:

• Increased frequency of fetal kicks, rolls, and hiccups.
• More noticeable Braxton‑Hicks “practice” contractions.
• Swollen ankles, lower‑back ache, and pelvic pressure.
• Changes in cervical mucus (often thicker or pink‑tinged).
• Occasional spotting or a small amount of vaginal discharge.

Even though you’re technically “full term,” the exact day of birth is still a mystery. Studies published by the CDC show that about 55 % of babies are born between 39 weeks 0 days and 40 weeks 6 days, with the median onset of labor at 40 weeks 3 days.

Difference between 39 and 40 weeks baby size

While a baby at 39 weeks is already well‑developed, by 40 weeks the average length grows from roughly 19.5 inches (49.5 cm) to about 20.2 inches (51.3 cm), and weight may increase by 0.2 lb (90 g). The differences are modest, but the extra week can improve lung maturity and reduce the risk of neonatal intensive‑care admission, according to ACOG.

Signs labor will start at 40 weeks

Common early‑labor signs include:

• Regular, increasingly painful contractions that tighten the uterus every 5–10 minutes and last 45–60 seconds.
• Rupture of membranes — a sudden gush or steady leak of fluid, often described as “water breaking.”
• Bloody‑tinged mucus (bloody show) indicating cervical changes.
• Increasing pelvic pressure as the baby drops lower.
• Lower‑back pain that becomes rhythmic and radiates to the abdomen.

False labor, or Braxton‑Hicks, can mimic these sensations but typically lacks a predictable pattern. The contractions are irregular, stop when you change position, and don’t intensify over time. A simple way to test: time the intervals between contractions. If they become closer together and stay consistent for an hour, you’re likely in true labor.

Average length of labor after 40 weeks varies. For first‑time mothers, the active phase (from 4 cm dilation to delivery) averages 13 hours, while for those who have given birth before it shortens to roughly 8 hours (ACOG). However, many women experience much shorter labors, especially if the baby is well‑positioned.

How to induce labor naturally at 40 weeks

If you reach 41 weeks without labor, your provider may discuss induction. Some women try natural methods earlier, such as:

• Walking or gentle exercise to encourage the baby’s descent.
• Sexual intercourse (prostaglandins in semen may help ripen the cervix).
• Membrane‑sweeping performed by a clinician during a prenatal visit.
• Acupressure or nipple stimulation (both increase oxytocin release).

Evidence from the NHS indicates these methods have modest success rates and are generally safe when you’re still at 40 weeks. Always discuss any approach with your provider before trying it.

How to prepare for delivery at 40 weeks

Preparation is both mental and logistical. A well‑thought‑out birth plan, a packed hospital bag, and a solid support network can reduce anxiety and keep you focused on the moment when labor begins.

Key steps include:

1. Review your birth plan with your provider. Decide on preferences for pain relief, mobility, fetal monitoring, and who will be present.
2. Finalize your hospital bag — see the checklist below.
3. Arrange transportation (e.g., a family member’s car, rideshare, or hospital shuttle).
4. Confirm your postpartum support — who will bring meals, help with the newborn, or run errands.
5. Practice relaxation techniques such as breathing, visualization, or gentle yoga, which can be useful during early labor.

What to pack in a hospital bag for 40 weeks pregnant

Pack the bag by the end of week 39 so you’re ready for any surprise early labor. Keep it somewhere accessible, like a bedside closet.

What are normal fetal movements at 40 weeks?

Fetal movement is a reassuring sign of your baby’s well‑being. At 40 weeks, you should feel at least 10 movements within a two‑hour window, often described as kicks, rolls, or gentle “punches.” The baby’s size means movements may feel more like nudges than strong kicks, especially when they’re low in the pelvis.

Monitoring tips:

• Pick a consistent time each day (e.g., after meals) to count movements.
• Lie on your side; this improves blood flow and makes kicks easier to feel.
• If you notice a sudden drop in activity—especially if it lasts an hour—call your provider right away.

Studies from the WHO recommend a “kick‑count” method as a reliable home screening tool. Most clinicians ask you to report any notable change in pattern, rather than a specific number, because each baby’s baseline can differ.

When to call the doctor at 40 weeks pregnant

Even though full term is a reassuring milestone, certain signs signal that you need immediate medical attention. Call your provider—or go to the nearest labor‑and‑delivery unit—if you experience any of the following:

• Regular contractions lasting more than a minute, occurring every 5 minutes or less.
• Rupture of membranes (a gush or steady leak of fluid).
• Vaginal bleeding heavier than spotting or bright red blood.
• Severe abdominal pain that doesn’t subside with rest.
• Sudden decrease in fetal movement.
• Fever (temperature ≥ 100.4 °F or 38 °C) or chills.

These red‑flag symptoms could indicate the onset of labor, infection, or other complications that need prompt evaluation.

Diet and nutrition tips for 40 weeks pregnant

Nutrition in the final week focuses on supporting both your energy levels and the baby’s last‑minute growth. Aim for balanced meals that include lean protein, whole grains, healthy fats, and plenty of fluids.

Key recommendations:

• Stay hydrated — aim for 8–10 cups of water daily. Dehydration can trigger Braxton‑Hicks contractions.
• Include iron‑rich foods (spinach, lentils, fortified cereals) to prevent anemia, which can cause fatigue.
• Calcium sources (yogurt, cheese, fortified plant milks) support bone health for both you and the baby.
• Omega‑3 fatty acids from salmon or walnuts aid the baby’s brain development.
• Limit high‑sugar snacks that can cause energy crashes and increase the risk of gestational diabetes flare‑ups.

If you’re experiencing constipation—a common issue at term—add soluble fiber (oats, fruit) and a daily probiotic yogurt. Gentle movement, like a short walk, can also help.

What tests are done at 40 weeks pregnancy

Most providers schedule a final prenatal visit around 39‑40 weeks. The appointment typically includes:

• Physical exam — measuring blood pressure, weight, and checking for edema.
• Fetal heart rate monitoring (non‑stress test) to ensure the baby’s heart is responding well.
• Ultrasound (if needed) to assess growth, placenta position, and amniotic fluid volume.
• Group B Streptococcus (GBS) screening (if not done earlier) to plan for intrapartum antibiotics.
• Blood tests for anemia, blood type, and rubella immunity if not already completed.

ACOG advises that a non‑stress test is optional for low‑risk pregnancies at 40 weeks, but many clinicians use it for reassurance. If any concerns arise—such as reduced fetal movement or abnormal blood pressure—additional testing, like a biophysical profile, may be ordered.

How to manage pain and discomfort at 40 weeks

Physical discomfort intensifies as the baby descends. Simple, doctor‑approved strategies can provide relief while you await labor.

• Prenatal massage (by a certified therapist) can ease back and hip pain.
• Warm compresses on the lower abdomen soothe Braxton‑Hicks.
• Gentle stretching and pelvic tilts improve circulation and reduce pressure.
• Heat‑wrapped socks or a warm foot soak can alleviate swelling.
• Hydration and small, frequent meals help maintain energy and prevent nausea.

If you’re experiencing more severe pain, discuss options such as acetaminophen (Tylenol) with your provider. Opioids are generally reserved for acute post‑delivery pain and are not recommended for routine use before labor.

Myth vs. fact

Myth: “If you haven’t gone into labor by 40 weeks, the baby is overdue and something is wrong.”

Fact: Reaching 40 weeks simply means the baby is full term. While many babies are born by then, it’s normal for labor to start a few days later. Your provider monitors both you and the baby to ensure health continues.

Myth: “You must stay in bed once you’re 40 weeks.”

Fact: Light activity, such as walking or gentle prenatal yoga, can promote circulation, reduce swelling, and potentially help the baby settle into the pelvis. Unless your provider advises bed rest for a specific reason, staying mobile is safe.

Myth: “You can’t eat after 40 weeks because the baby will grow too large.”

Fact: A balanced diet remains crucial. Overeating isn’t a concern, but maintaining nutritious meals supports your energy and the baby’s final growth spurts.

Key takeaways

• At 40 weeks you’re officially full term; most babies are ready to be born.
• Watch for regular, painful contractions, water breaking, or a sudden drop in fetal movement — these are signs to call your provider.
• Pack your hospital bag by the end of week 39 so you’re prepared for any early labor.
• Stay hydrated, eat balanced meals, and use gentle stretches to ease discomfort.
• Your final prenatal visit will include a blood pressure check, fetal heart monitoring, and possibly a non‑stress test.
• If you reach 41 weeks without labor, discuss induction options with your provider.

Frequently asked questions

How many weeks is a full‑term pregnancy?

Full term is defined as 39 weeks 0 days through 40 weeks 6 days, according to ACOG.

What are the signs that labor is starting?

Regular contractions every 5 minutes, a gush of fluid, bloody‑tinged mucus, and increasing pelvic pressure are classic early‑labor signs.

When should I call my doctor at 40 weeks?

Call immediately for strong, regular contractions, water breaking, heavy bleeding, severe pain, fever, or a noticeable drop in baby kicks.

Can a baby be born after 40 weeks?

Yes. Babies can be born safely up to 42 weeks, though providers often discuss induction after 41 weeks to reduce risks.

What tests are done at 40 weeks?

Typical tests include a blood pressure check, fetal heart rate monitoring, possibly a non‑stress test, and a final GBS screen.

How can I tell if I’m in false labor?

False labor (Braxton‑Hicks) features irregular, non‑progressive contractions that often stop when you change position, unlike true labor which becomes more rhythmic and intense.

When to call your doctor

If you notice any of the following, seek medical care right away: regular painful contractions, a sudden gush of fluid, heavy vaginal bleeding, severe abdominal pain, fever, or a significant decrease in fetal movement. This article provides general information and is not a substitute for personalized medical advice.

From our medical team: “Reaching 40 weeks is a milestone, but every day can bring new sensations. Trust your body’s signals, keep your support team close, and don’t hesitate to reach out if anything feels off. Your provider is there to guide you safely through labor and beyond.”

References

1. American College of Obstetricians and Gynecologists. “Full Term Pregnancy.” ACOG Practice Bulletin, 2023.
2. National Health Service (NHS). “Labour and delivery: what to expect.” Updated 2022.
3. Centers for Disease Control and Prevention (CDC). “Births: Data & Statistics.” 2022.
4. World Health Organization. “WHO recommendations on antenatal care for a positive pregnancy experience.” 2016.
5. Maternal‑Fetal Medicine Unit, Mayo Clinic. “Non‑stress test (NST) in pregnancy.” 2021.
6. Royal College of Obstetricians and Gynaecologists (RCOG). “Guidelines on induction of labour.” 2020.
7. Harvard Medical School. “Fetal movement counting.” Harvard Health Publishing, 2023.
8. University of California, San Francisco (UCSF) Health. “Nutrition during pregnancy.” 2022.
9. American Academy of Pediatrics (AAP). “Postpartum care for mothers and newborns.” 2021.
10. National Institute for Health and Care Excellence (NICE). “Labor and delivery guidelines.” 2022.