33 weeks pregnant

33 weeks pregnant is about 7½ months. It falls in the eighth month of pregnancy. You are in week 33 of 40, in the third trimester. Here is what is happening with your baby and your body this week.

Your baby at 33 weeks

The immune system is developing, and the baby is receiving antibodies from you.

Your baby's skull bones are still separate and can overlap slightly, which lets the head mold during birth. The soft spots, called fontanelles, stay open after birth so the brain has room to keep growing during the first years of life. Other bones in the body are hardening and getting stronger.

Antibodies passing across the placenta now will give your baby some protection against infections in the first months after birth. This is one reason some vaccines are recommended during pregnancy, so ask your provider which ones apply to you.

The pupils can now narrow and widen in response to light, and your baby spends a lot of time in active sleep, the stage linked with brain development. Babies vary widely in size near term, and growth tends to follow a family pattern as well.

Your body at 33 weeks

Your joints may feel looser because of pregnancy hormones. Swelling may increase.

The hormone relaxin is loosening the ligaments in your pelvis to prepare for birth, but it can also make your joints feel unstable and cause pain at the front of the pelvis or in the hips, especially when walking, climbing stairs, or turning over in bed. Keeping your knees together when getting in and out of the car or bed may help. If pelvic pain is limiting how you move, ask your doctor or midwife about a referral to a physical therapist. Sleep can also be harder now, with vivid dreams and frequent waking common.

Your belly at week 33

In month 8 (weeks 32–35) the uterus reaches its highest point, up near your ribs, so breathlessness and heartburn are common. Fundal height is usually around 32–35 cm.

Belly size and shape vary a lot depending on your build, whether this is your first pregnancy, your baby's position and the amount of amniotic fluid. At checkups your doctor or midwife may measure your fundal height to track your baby's growth, and may arrange an ultrasound if the measurement is quite different from what they expect.

Symptoms at 33 weeks pregnant

• Pelvic or hip pain, sometimes with a clicking feeling
• Swelling in the feet, ankles, and hands
• Disrupted sleep and vivid dreams
• Clumsiness or feeling off balance
• Mild backache

Checkups around week 33

Prenatal visits are often every two weeks at this stage, but schedules vary by country. Expect blood pressure and urine checks, which help screen for preeclampsia, plus measurement of your bump and a check of your baby's heartbeat. Some people are offered a whooping cough or RSV vaccine in the third trimester, depending on local guidance and the time of year.

Common symptoms in the third trimester

The third trimester runs from week 28 until birth, usually around week 40. Your baby gains most of their weight, their lungs mature, and your body prepares for labor. Not everyone has every symptom, and it is normal for symptoms to come and go. Common ones include:

• Shortness of breath as your uterus presses up on your diaphragm
• Braxton Hicks (practice) contractions
• Swelling of the feet and ankles
• Trouble sleeping and getting comfortable
• Pelvic pressure and pain
• Needing to urinate more often again
• Heartburn and back ache

Read the full third trimester guide.

When to call your doctor or midwife

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Frequently asked questions

How big is my baby at 33 weeks pregnant?

At 33 weeks pregnant, your baby is about the size of a pineapple. That is about 43.7 cm (17.2 in) from crown to heel, weighing about 1.9 kg (4.2 lb).

How big is my belly at week 33 of pregnancy?

In month 8 (weeks 32–35) the uterus reaches its highest point, up near your ribs, so breathlessness and heartburn are common. Fundal height is usually around 32–35 cm. Bump size, shape and when you start to show vary a lot from person to person.

Is pelvic pain normal at 33 weeks pregnant?

Some pelvic discomfort is common now as your joints loosen and your baby gets heavier. Pain at the front of the pelvis that worsens with walking or rolling over may be pelvic girdle pain, which can be helped with physical therapy, support, and pacing yourself. Pain that comes in regular waves, or comes with bleeding, fluid loss, or fever, needs prompt medical advice.

Why are my hands and feet swollen at 33 weeks?

Mild swelling is common in late pregnancy because your body holds more fluid and your uterus slows blood flow back from your legs. Resting with your feet up and staying active can help. However, sudden swelling of the face, hands, or feet, especially with a headache or vision changes, can be a sign of preeclampsia and should be checked by your provider right away.

Should I get vaccinated at 33 weeks pregnant?

Vaccines given in the third trimester, such as the whooping cough vaccine, help your body make antibodies that pass to your baby and protect them in the first weeks of life. Depending on where you live and the season, an RSV vaccine may also be offered within a specific window. Recommendations differ by country, so talk to your doctor or midwife about which vaccines are right for you.

What trimester is 33 weeks pregnant?

Week 33 is in the third trimester, which covers weeks 28 to 40.

How many months is 33 weeks pregnant?

33 weeks pregnant is about 7½ months. It falls in the eighth month of pregnancy. The eighth month covers weeks 32 to 35. Pregnancy is about 40 weeks, or roughly 9 months, counted from the first day of your last period.

This page is general educational information and is not a substitute for advice from your doctor or midwife. Every pregnancy is different, and baby sizes are approximate averages. Last updated 2026-11-07. See our medical disclaimer.