Pregnancy Week 33
Your baby continues to gain weight and become stronger this week. The brain is developing rapidly, the immune system is becoming more active, and the lungs continue to mature. Your baby is also gaining more body fat and preparing for the final weeks of pregnancy.
Your Baby This Week
Brain Development
Your baby’s brain continues developing rapidly during week 33. The brain is becoming increasingly complex as nerve cells form and strengthen connections.
These developments help your baby coordinate movements and process sounds and other sensations.
Developing Immune System
Your baby’s immune system continues developing as pregnancy progresses.
Antibodies from you also cross the placenta and provide your baby with important passive immune protection that will continue to support your baby after birth.
More Body Fat
Your baby continues accumulating fat beneath the skin. This gives the body a fuller appearance and provides an important energy reserve.
The additional fat will also help your baby regulate body temperature after birth.
Lung Maturation
The lungs continue developing and producing increasing amounts of surfactant.
The airways and structures needed for breathing continue maturing, although the lungs are still developing during these final weeks.
Growing & Getting Stronger
Your baby is about the size of a pineapple. The brain and immune system continue developing while the lungs mature and your baby gains more fat and weight.
Your Body This Week
Your body continues adapting as your baby grows and the third trimester progresses.
Growing Belly
Your uterus continues expanding and may put increasing pressure on your bladder, stomach, and other organs.
Stronger Baby Movements
Your baby's movements may feel stronger and more predictable. Although there is less room for large movements, you should continue to notice your baby's usual activity.
Heartburn & Indigestion
Heartburn, bloating, and indigestion can become more noticeable as the growing uterus puts pressure on the digestive system.
Swelling
Mild swelling of the feet and ankles can occur during pregnancy, especially after standing or sitting for long periods. Sudden or significant swelling, particularly of the face or hands, should be discussed promptly with your healthcare professional.
Tips for week 33
- Continue taking your prenatal vitamin every day.
- Eat balanced meals containing protein, vegetables, fruits, whole grains, and healthy fats.
- Include iron-rich foods regularly.
- Choose calcium-rich foods to support your baby's developing bones.
- Include healthy sources of omega-3 fatty acids.
- Eat plenty of fiber-rich foods.
- Drink plenty of water throughout the day.
- Avoid standing or sitting in one position for long periods.
- Elevate your feet when resting if you experience mild swelling.
- Eat smaller meals if heartburn is bothering you.
- Continue pregnancy-safe physical activity if approved by your healthcare professional.
- Use pillows to support your abdomen, back, and legs while sleeping.
- Get enough rest.
- Avoid alcohol, smoking, and recreational drugs.
- Limit caffeine to 200 mg or less per day during pregnancy.
- Keep your prenatal appointments.
- Follow your healthcare professional's guidance regarding fetal movement and third-trimester monitoring.
Nutrition This Week
Your baby’s brain, immune system, lungs, bones, and rapidly growing body continue requiring a wide range of nutrients.
Omega-3 Fatty Acids
Iron Rich Foods
Calcium Sources
Protein Rich Foods
Folate Rich Foods
Healthy Fats
Fruits & Vegetables
Whole Grains
Stay Hydrated
Nutrition Tip
Continue choosing nutrient-dense foods rather than relying on highly processed snacks. A varied diet provides the nutrients needed to support your baby’s continued brain, immune, and physical development.
Frequently Asked Questions
How big is my baby at Week 33?
Technically, pregnancy has not started yet. Week 1 is counted from the first day of your last menstrual period (LMP), which doctors use to calculate your due date.
What is developing during Week 33?
Your baby’s brain continues developing rapidly, the immune system is becoming more active, and the lungs continue maturing. Your baby is also gaining more body fat and weight.
Does my baby have an immune system?
Yes. Your baby’s immune system is developing, and antibodies from you cross the placenta to provide passive immune protection.
Are my baby's movements supposed to change?
As your baby grows and space becomes more limited, movements may feel different. You may notice more rolls, stretches, kicks, and pressure rather than large changes in position.
Is my baby likely to be head-down at Week 33?
Many babies are moving toward a head-down position during the third trimester, but babies can still change position at this stage. Your healthcare professional can assess your baby’s position.
Is swelling normal during pregnancy?
Mild swelling of the feet and ankles can be common, especially later in pregnancy. However, sudden or significant swelling, especially involving the face or hands, should be evaluated by a healthcare professional.
What happens if my baby is born at Week 33?
A baby born at 33 weeks is considered preterm and may need specialized neonatal care. The level of support required varies from baby to baby, and outcomes generally improve as pregnancy progresses.
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