33 Weeks Pregnant: What to Expect for You and Your Baby

Quick take: At 33 weeks you’re in the home stretch of pregnancy. Your baby is about the size of a pineapple, gaining weight rapidly, and practicing breathing movements. You may feel stronger aches, Braxton‑Hicks contractions, and a growing need for rest, but most routine tests are still on schedule and gentle exercise remains safe for most moms. Use this guide to know what’s normal, what to prepare for, and when to reach out to your provider.

It’s late evening, the baby’s kicking feels like tiny hiccups, and you’re scrolling through a sea of “33 weeks pregnant what to expect” articles. You’ve probably already Googled the baby’s size, wondered about that lingering soreness in your lower back, and started thinking about what goes in your hospital bag. You’re not alone—many moms‑to‑be share that mix of excitement and anxiety at this stage.

In the next few minutes we’ll walk through the key milestones for you and your little one, break down weight‑gain targets, list the symptoms you might notice, and give you a practical checklist for the weeks ahead. We’ll also cover travel, sleep, exercise, and the tests that keep you on track, all backed by guidance from ACOG, the NHS, and other trusted health bodies.

By the end of this article you’ll have a clear picture of where you stand at 33 weeks, a ready‑to‑use hospital‑bag list, and confidence about what’s normal versus what warrants a call to your provider.

What are the baby’s development milestones at 33 weeks?

By the time you’re 33 weeks along, your baby is roughly 17.5 inches (44 cm) long and weighs about 4.5 lb (2,040 g). Think of a ripe pineapple or a small cantaloupe—that’s the size you’ll see on the ultrasound. The brain is firing billions of neurons per second, and the lungs are forming the alveoli that will soon fill with air. The baby can now open and close its eyes, respond to light, and even suckle reflexes are developing, a good sign for post‑birth feeding.

During the 33‑week ultrasound, you’ll likely see a detailed picture of the head circumference, femur length, and amniotic fluid volume. The sonographer may also check the placenta’s position and assess growth trends compared with earlier scans. If the baby’s measurements fall within the 10th‑90th percentile for gestational age, that’s reassuring; any concerns will be followed up with a growth‑scan later in the third trimester.

At this stage, your baby is getting ready for life outside the womb by accumulating a layer of fat under the skin, which helps with temperature regulation after birth. Their bones are continuing to harden, though the skull bones remain soft and flexible to allow for passage through the birth canal. The baby's immune system is also receiving antibodies from you, providing crucial protection against infections in their first few months.

Developmentally, the baby is mastering the coordination needed for breathing. Although the lungs are not fully mature, the surfactant—a substance that keeps the air sacs from collapsing—is being produced in larger amounts. This is why many hospitals keep a neonatal intensive‑care unit (NICU) nearby, just in case a preterm birth happens before 37 weeks.

Most importantly, the baby’s reflexes are becoming more purposeful. The startle (Moro) reflex may still appear, and the baby can now turn its head toward a gentle touch on the belly. These signs reassure clinicians that the nervous system is progressing well. Your baby is also developing distinct sleep-wake cycles, which you might notice as periods of intense movement followed by quiet spells. Their senses are also sharpening; they can hear your voice and recognize familiar sounds, so talking and singing to your bump is a wonderful way to bond.

How much weight should I gain by 33 weeks pregnant?

• Underweight (BMI < 18.5): 28–40 lb (12.5–18 kg)
• Normal weight (BMI 18.5–24.9): 25–35 lb (11.5–16 kg)
• Overweight (BMI 25–29.9): 15–25 lb (7–11.5 kg)
• Obese (BMI ≥ 30): 11–20 lb (5–9 kg)

By week 33, most women have reached about 80–90 % of their total target. For a woman with a normal pre‑pregnancy BMI, that translates to roughly 20–23 lb (9–10.5 kg) gained so far. If you’re tracking weekly weight on a scale, aim for a steady gain of about 0.5–1 lb (0.2–0.45 kg) per week during the second and early third trimesters, then a slightly slower pace as you near term.

Nutrition matters as much as the number on the scale. The NHS advises increasing calories by about 300 kcal per day in the third trimester, focusing on nutrient‑dense foods: lean proteins, whole grains, leafy greens, and healthy fats. Calcium‑rich dairy or fortified alternatives, iron‑rich legumes, and omega‑3 sources like low‑mercury fish support fetal bone and brain development. These extra calories should come from wholesome sources to fuel your baby's rapid growth and your own energy needs, rather than empty calories that can lead to excessive weight gain and discomfort.

Conversely, certain foods should be avoided to reduce infection risk and limit excess calories. Stay away from unpasteurized cheeses, deli meats unless heated, and high‑mercury fish such as swordfish or king mackerel. Limit sugary drinks and processed snacks; they add calories without essential nutrients and can exacerbate gestational diabetes risk. Managing cravings with healthier alternatives, like fruit for sweets or air-popped popcorn for salty snacks, can help maintain a balanced diet without feeling overly restrictive.

Staying hydrated is essential. Aim for at least 8–10 cups of water daily, more if you’re active or live in a hot climate. Hydration helps maintain amniotic fluid volume, reduces swelling, and can even help prevent Braxton Hicks contractions from becoming too uncomfortable. Keep a water bottle handy throughout the day as a visual reminder to sip regularly.

Common symptoms and discomforts at 33 weeks pregnancy

As the baby grows, your body feels the change. Common complaints at 33 weeks include:

• Back and pelvic pressure: The uterus’s weight shifts your center of gravity, stressing the lower back and pelvis. This can manifest as dull aches or sharp pains, especially after standing or walking for extended periods.
• Shortness of breath: The expanding uterus presses on the diaphragm, making deep breaths feel shallow. This is normal and often eases a bit if the baby "drops" lower into the pelvis in the coming weeks.
• Braxton Hicks contractions: “Practice” pains that may start earlier but often become more noticeable now. They are typically irregular and don’t increase in intensity.
• Heartburn and indigestion: Hormonal relaxation of the lower esophageal sphincter combined with the uterus’s upward pressure. This can be quite uncomfortable, especially at night.
• Frequent urination: The baby’s head can press on the bladder, especially when lying flat. You might find yourself making many trips to the bathroom, day and night.
• Leg cramps and swelling: Fluid retention and pressure on veins can cause calf cramps and ankle edema. Elevating your legs can provide some relief.
• Fatigue: Despite being in the third trimester, many women experience a return of first-trimester-like exhaustion. Growing a human is hard work!
• Carpal tunnel syndrome: Swelling can put pressure on nerves in your wrists, leading to numbness, tingling, or pain in your hands and fingers.
• Hemorrhoids: Increased pressure on rectal veins and constipation can lead to hemorrhoids, which can be itchy, painful, or bleed.
• Increased vaginal discharge: It's normal to have more thin, milky white discharge (leukorrhea) as your body prepares for birth.

Braxton Hicks typically begin in the second trimester, but many women notice a clearer pattern around 33 weeks. They feel like a tightening band around the abdomen that lasts 30 seconds to a few minutes and usually eases without any cervical change. If the contractions become regular, intensify, or are accompanied by bleeding, it may signal true labor—see the “Signs of preterm labor” section.

Sleep can become a challenge. The ACOG recommends sleeping on your left side after week 20 to improve blood flow to the placenta and reduce pressure on the vena cava. If you’ve been a back‑sleeper, try propping a pillow behind your back or using a pregnancy pillow to keep you comfortably on your side. Experiment with different pillow arrangements to support your growing belly and hips for maximum comfort.

Heartburn can be mitigated by eating smaller meals, avoiding spicy or fatty foods, and staying upright for at least an hour after meals. A glass of water with a splash of almond milk can soothe the esophagus without adding too much acidity. Over-the-counter antacids, approved by your provider, can also offer relief.

Leg cramps often improve with gentle stretching before bed, staying well‑hydrated, and ensuring adequate magnesium intake through leafy greens, nuts, or a prenatal supplement approved by your provider. For back and pelvic pain, consider a supportive maternity belt, warm baths, or gentle prenatal massage. Remember, while these discomforts are common, you don't have to suffer in silence; discuss them with your provider for personalized advice.

What tests and appointments are scheduled at 33 weeks?

By the 33‑week mark, most prenatal schedules include a routine check‑up every four weeks until week 36, then every two weeks until delivery. Typical components of the 33‑week visit are:

• Blood pressure and weight check: To monitor for pre‑eclampsia and appropriate weight gain.
• Fetal heart rate assessment: Using a Doppler to ensure a steady rate of 110–160 bpm.
• Fundal height measurement: To gauge growth; the uterus should be roughly the same number of centimeters as the gestational age.
• Urine analysis: Checks for protein, glucose, and infection.
• Discussion of birth plan: Review preferences for pain management, delivery location, and support people.
• Mental health screening: Many providers now routinely screen for symptoms of anxiety or depression, recognizing the increased vulnerability during pregnancy.

Many providers also schedule a third‑trimester anatomy scan if one was not done at 20 weeks. This ultrasound looks at the baby’s growth, the placenta’s location, and amniotic fluid volume. The CDC notes that a growth scan is especially useful for mothers with diabetes, hypertension, or a history of growth‑restriction. Your provider might also discuss the importance of monitoring fetal movement, often referred to as "kick counts," as a simple way to assess your baby's well-being between appointments.

Dental health remains important. The American Dental Association (ADA) advises a routine cleaning at any stage of pregnancy, as hormonal changes increase gum inflammation. If you haven’t had a cleaning in the last six months, schedule one now—there’s no evidence that a dental cleaning harms the fetus. Good oral hygiene helps prevent gingivitis and periodontitis, which have been linked to adverse pregnancy outcomes.

Vaccinations are another consideration. If you haven’t received the Tdap vaccine (whooping cough) during pregnancy, the CDC recommends it between weeks 27 and 36 to protect the newborn for the first two months of life. This timing ensures that you pass on maximum antibodies to your baby before birth. Your provider may also discuss the flu shot if you haven't received it yet, as pregnant women are at higher risk for severe flu complications.

Finally, if you have a high‑risk pregnancy (e.g., prior pre‑term birth, gestational diabetes, or hypertension), your provider may order additional labs such as a glucose tolerance test or a non‑stress test (NST) to assess fetal well‑being. Around 35-37 weeks, you will also be screened for Group B Streptococcus (GBS), a common bacterium that can be passed to the baby during birth, requiring antibiotic treatment during labor if positive.

Fetal movement and kick counts at 33 weeks

As your baby grows, their movements become more distinct. At 33 weeks, you might feel strong kicks, jabs, and even stretches. While there's no magic number for "normal" movement, most healthcare providers recommend getting to know your baby's usual pattern of activity. The ACOG suggests that you choose a time of day when your baby is usually active and count how long it takes to feel 10 movements (kicks, flutters, swishes, or rolls). This usually takes less than 2 hours.

Tracking kick counts is a simple, non-invasive way to monitor your baby's well-being daily. Many apps are available to help you track. If you notice a significant decrease in your baby's usual movements, or if it takes longer than 2 hours to feel 10 movements, it's important to contact your healthcare provider immediately. Don't try to stimulate your baby with food or drinks to get them to move more; a sudden change in movement warrants immediate medical attention to rule out any potential issues. It's better to be safe than sorry when it comes to fetal well-being.

Signs of preterm labor at 33 weeks pregnant

Preterm labor is defined as regular uterine contractions that cause cervical change before 37 weeks. While many Braxton Hicks contractions are harmless, you should call your provider promptly if you notice any of the following “red‑flag” signs:

• Contractions that occur every 5 minutes or less, lasting more than 30 seconds, and becoming stronger or more painful.
• Increasing vaginal discharge that’s watery, mucous‑filled, or tinged with blood.
• Persistent lower‑back or pelvic pressure that doesn’t ease with rest or position change.
• Sudden gushes or a steady leak of fluid (possible amniotic‑fluid leak).
• Fever over 100.4 °F (38 °C) without an obvious cause.
• Abdominal cramping with or without diarrhea.

If you experience any of these symptoms, especially in combination, contact your obstetrician, midwife, or go to the nearest labor‑and‑delivery unit. Early intervention—often with steroids to accelerate fetal lung maturity—can dramatically improve outcomes for babies born before 34 weeks. Your provider will assess your condition, perform a cervical exam, and may monitor your contractions and the baby's heart rate.

For most mothers, the transition from Braxton Hicks to true labor is gradual. Keeping a simple log of contraction timing, intensity, and accompanying symptoms can help your provider assess whether you’re entering active labor. Risk factors for preterm labor can include a history of preterm birth, carrying multiples, certain uterine or cervical abnormalities, and some infections, but often preterm labor occurs without an identifiable cause. Knowing the signs is your best defense.

Preparing for labor: what to pack in a hospital bag at 33 weeks?

Starting your packing early reduces stress when the due date arrives. Aim to have most items ready by the end of week 36, but you can begin assembling the core list now. Here’s a practical checklist:

• For you: Comfortable maternity‑day gown or loose‑fitting shirt, nursing bras (2–3), a pair of slippers, socks, and a robe. Don't forget comfortable postpartum underwear (disposable or high-waisted cotton) and heavy-duty maternity pads.
• Personal care: Toothbrush, toothpaste, hairbrush, gentle shampoo, lip balm, and a travel‑size moisturizer (skin can get dry). Also pack any prescription medications you take regularly, and a few hair ties.
• Documents: Insurance card, ID, birth plan (if you have one), and a list of emergency contacts. Pre-registering at the hospital can also save time during admission.
• For baby: Newborn onesies (size 0 and 1), a soft blanket, a hat, and a going‑home outfit. Ensure you have a properly installed car seat for the ride home – this is often checked by hospital staff before discharge.
• Entertainment & comfort: Phone charger, headphones, a playlist of calming music, and a pillow with a washable cover. A book or tablet can also be helpful for downtime.
• Snacks & drinks: Light, easy‑to‑digest snacks (granola bars, fruit, crackers) and a bottle of water; many hospitals limit meals during active labor, but snacks are often allowed for support persons.

If you have a birth partner, ask them to pack an extra change of clothes, toiletries, and any personal items they’ll need for a long stay. They might appreciate their own pillow, a blanket, and some entertainment options too. Having their bag ready minimizes distractions and allows them to focus on supporting you.

Don’t forget to check the hospital’s policies on visitors, parking, and what they provide (e.g., most hospitals supply diapers, but you may prefer a specific brand). Knowing these details in advance can prevent surprises and make your stay more comfortable. Consider also packing items for postpartum recovery, such as perineal spray, witch hazel pads, or a peri bottle, as these can make the initial days post-birth much more manageable.

Is it safe to exercise at 33 weeks pregnant?

For most low‑risk pregnancies, the ACOG recommends at least 150 minutes of moderate‑intensity aerobic activity each week, even in the third trimester. Safe options include walking, swimming, stationary cycling, and prenatal yoga. The key is to keep intensity at a level where you can talk comfortably—often called the “talk test.” Regular exercise can not only help manage common discomforts like back pain and swelling but also improve sleep, boost mood, and even prepare your body for the physical demands of labor and delivery.

When exercising, stay mindful of a few modifications:

• Avoid activities with a high risk of falling or abdominal trauma, such as contact sports, downhill skiing, or horseback riding.
• Steer clear of supine positions after week 20; lying flat on your back can compress the vena cava and reduce blood flow to the baby. Modify exercises to an incline or side-lying position.
• Stay hydrated and wear supportive shoes to reduce swelling and prevent dizziness. Carry a water bottle and sip frequently.
• Listen to your body—if you feel sharp pain, excessive shortness of breath, dizziness, vaginal bleeding, or fluid leakage, stop and call your provider.

Traveling by plane is generally considered safe up to 36 weeks for uncomplicated pregnancies, according to the American College of Obstetricians and Gynecologists. Airlines often require a medical certificate after 28 weeks, so obtain one from your provider if you plan to fly. Stay hydrated, move your legs every hour, and consider a compression stocking to lower the risk of deep‑vein thrombosis. Always check with your airline for their specific policies before booking.

Strength training can continue with light weights (≤ 5 lb) or resistance bands, focusing on maintaining posture and core stability. Avoid heavy lifting (> 25 lb) and exercises that strain the abdominal wall, such as full sit‑ups. Instead, focus on pelvic floor exercises and gentle core work that supports your growing belly. Modifications like wall push-ups instead of floor push-ups can keep you active safely.

Overall, staying active can help reduce back pain, improve sleep, and prepare your muscles for labor. If you’re unsure about a specific activity, discuss it at your next prenatal visit. Remember, the goal is to maintain your fitness, not to achieve new personal bests.

Emotional well-being and nesting at 33 weeks

The third trimester often brings a rollercoaster of emotions. Excitement for meeting your baby can be intertwined with anxiety about labor, delivery, and the immense changes ahead. It's completely normal to feel a mix of joy, nervousness, impatience, and even a bit of fear. Many women also experience a strong urge to "nest" around this time – a powerful instinct to clean, organize, and prepare the home for the baby's arrival. This can be a productive way to channel your energy, but it's important not to overdo it.

Take time for self-care and emotional preparation. Talk openly with your partner, friends, or family about your feelings. Consider joining a prenatal class or support group, where you can connect with other expectant parents and share experiences. Practicing mindfulness, meditation, or gentle prenatal yoga can also help manage stress and anxiety. The NHS emphasizes the importance of mental well-being during pregnancy, noting that seeking support for anxiety or depression is a sign of strength, not weakness.

While nesting can be fulfilling, remember to prioritize rest and avoid heavy lifting or strenuous tasks. Delegate chores where possible, and focus on enjoyable preparations like decorating the nursery or washing baby clothes. If feelings of anxiety or sadness become overwhelming, persistent, or interfere with your daily life, please reach out to your healthcare provider. They can offer support, resources, or refer you to a mental health professional who specializes in perinatal care.

Car seat safety and installation

One of the most crucial preparations for bringing your baby home is ensuring you have a safe and properly installed car seat. This is often an overlooked detail until the last minute, but it’s essential to get it right well before your due date. The American Academy of Pediatrics (AAP) recommends installing your infant car seat and having it inspected by a certified Child Passenger Safety Technician (CPST) before your baby arrives, ideally by 36 weeks.

There are three main types of car seats for infants: infant-only seats, convertible seats, and all-in-one seats. For newborns, infant-only seats are typically recommended as they are designed for smaller babies and can be easily carried in and out of the car. Regardless of the type, the car seat must be installed rear-facing in the back seat of your vehicle. Never place a rear-facing car seat in the front seat where there is an active airbag.

Proper installation can be tricky, with common mistakes including loose installation, incorrect harness height, or improper angle. Many hospitals will not discharge your baby until they see a properly installed car seat. To find a certified CPST in your area, you can visit safecar.gov (US) or check local fire departments, police stations, or hospitals. They can provide hands-on assistance and ensure your car seat is installed correctly and safely for your little one's first ride home.

From our medical team: At 33 weeks, it's common for expectant parents to feel a surge of emotions, from excitement to apprehension. Remember, your body is doing incredible work, and it's okay to slow down and prioritize your well-being. Focus on healthy habits, listen to your body, and don't hesitate to voice any concerns, big or small, to your healthcare provider. We're here to support you every step of the way.

Myth vs. fact

Myth: At 33 weeks you should already feel the baby move constantly.

Fact: While many babies are active, movement patterns can vary daily. A sudden decrease in kicks warrants a call, but occasional quiet periods are normal. What matters most is knowing your baby's unique pattern and reporting any significant changes.

Myth: You must stop all exercise after the halfway point.

Fact: Moderate, low‑impact activity is encouraged by ACOG through the third trimester unless you have a specific medical restriction. Exercise offers many benefits for both you and your baby.

Myth: You can’t travel by air after the second trimester.

Fact: Most airlines allow travel up to 36 weeks for uncomplicated pregnancies; always get a clearance letter from your provider and check airline policies, as requirements can vary.

Myth: Heartburn means your baby will have a lot of hair.

Fact: While some studies suggest a correlation, heartburn is primarily caused by hormonal changes and the physical pressure of your growing uterus on your stomach, not directly by fetal hair growth. It’s a common pregnancy symptom.

Key takeaways

• By 33 weeks the baby is about the size of a pineapple, rapidly gaining weight, and practicing breathing movements.
• Aim for a total weight gain that matches your pre‑pregnancy BMI; most have reached ~80 % of the goal by now through nutrient-dense foods.
• Common symptoms include back pressure, Braxton‑Hicks contractions, heartburn, and increased fatigue—manage them with posture, small meals, rest, and support.
• Regular prenatal visits, a growth ultrasound, Tdap vaccine, and GBS screening are typical at this stage.
• Begin tracking fetal movements daily; a significant decrease in kick counts warrants immediate contact with your provider.
• Call your provider if you notice regular painful contractions, fluid leakage, or bleeding, as these could be signs of preterm labor.
• Gentle exercise, such as walking or swimming, remains safe; airline travel is allowed up to 36 weeks with a provider’s note.
• Start packing your hospital bag now, including essential postpartum items for yourself and a properly installed car seat for the baby.
• Prioritize your emotional well-being; it's normal to feel a mix of excitement and anxiety. Don't hesitate to seek support if needed.

Frequently asked questions

How big is the baby at 33 weeks?

The baby measures roughly 17.5 inches (44 cm) in length and weighs about 4.5 lb (2 kg), comparable to a pineapple. They are rapidly gaining weight and developing a fat layer under the skin.

What are the signs of labor at 33 weeks?

Regular contractions every 5 minutes or less, persistent pelvic pressure, vaginal discharge with blood or fluid, or a sudden gush of fluid signal possible preterm labor and should be reported immediately to your provider.

Can I still exercise at 33 weeks pregnant?

Yes—moderate aerobic activity like walking, swimming, or prenatal yoga is safe for most women; avoid high‑impact or contact sports, modify exercises to avoid lying flat on your back, and always listen to your body.

Is it safe to have a dental cleaning at 33 weeks?

Dental cleanings are safe throughout pregnancy, and the ADA recommends a routine visit to prevent gum disease, which can affect pregnancy outcomes. Inform your dentist you are pregnant.

When should I start packing my hospital bag?

Begin assembling core items now and aim to have the bag ready by week 36, so you’re prepared for an unexpected early labor. Don't forget items for your partner and for your postpartum recovery.

What should I eat during the third trimester at 33 weeks?

Focus on nutrient‑dense foods: lean protein, whole grains, leafy greens, calcium‑rich dairy or alternatives, and omega‑3 sources while limiting high‑mercury fish, unpasteurized cheeses, and excessive sugary snacks. Hydration is also key.

How do I do kick counts at 33 weeks?

Choose a time when your baby is typically active and count how long it takes to feel 10 movements. If it takes longer than 2 hours, or if you notice a significant decrease in your baby's usual movement pattern, contact your provider right away.

When should I install my car seat?

It's recommended to install your infant car seat and have it checked by a certified Child Passenger Safety Technician (CPST) by 36 weeks pregnant. This ensures it's correctly installed and ready for your baby's first ride home.

When to call your doctor

Contact your provider right away if you experience any of the following: regular painful contractions (every 5 minutes or less), vaginal bleeding or fluid leakage, sudden severe abdominal pain, fever over 100.4 °F (38 °C) without an obvious cause, a noticeable decrease in fetal movement (fewer than 10 movements in 2 hours during an active period), severe or persistent headaches, vision changes, or sudden swelling in your face or hands.

This article provides general information and is not a substitute for personalized medical advice. Always consult your healthcare professional with any specific concerns.

References

1. American College of Obstetricians and Gynecologists (ACOG). “Weight Gain During Pregnancy.” Clinical Guidance, 2023.
2. National Health Service (NHS). “Pregnancy week by week – 33 weeks.” UK Government Health Guidance, 2022.
3. Centers for Disease Control and Prevention (CDC). “Pregnancy and Tdap Vaccination.” Immunization Recommendations, 2023.
4. World Health Organization (WHO). “Maternal health: Antenatal care.” Global Guidelines, 2021.
5. American Dental Association (ADA). “Oral Health Care During Pregnancy.” Clinical Recommendations, 2022.
6. Mayo Clinic. “Braxton Hicks contractions.” Patient Care Information, 2023.
7. Royal College of Obstetricians and Gynaecologists (RCOG). “Travel in pregnancy.” Clinical Practice Guidelines, 2022.
8. U.S. Food and Drug Administration (FDA). “Pregnancy and Lactation Labeling.” Drug Safety Updates, 2023.
9. American College of Obstetricians and Gynecologists (ACOG). “Fetal Movement Counting.” Patient Education, 2023.
10. American Academy of Pediatrics (AAP). “Car Seats: Information for Families.” Safety & Prevention, 2023.