How Your Body Changes During Pregnancy: A Month-by-Month Guide to the Journey

Pregnancy is one of the most remarkable transformations a human body can experience. While the growing bump may be the most visible change, there are dozens of other powerful shifts happening - from head to toe, and inside out.

Understanding these changes isn’t just helpful - it’s empowering. Knowing what to expect can ease anxiety, help you tune into your body’s signals, and guide you to make supportive choices along the way.

Let’s explore some of the key changes your body undergoes throughout pregnancy.

1st Trimester (Weeks 1–12): Hormonal Shifts and Early Adaptations

What’s happening:

• Hormones surge: Estrogen and progesterone increase rapidly, helping maintain the pregnancy and supporting the development of the placenta.

• Fatigue & nausea: Your body is using massive amounts of energy to form vital structures, which can leave you feeling completely drained.

• Breast tenderness: Glands begin preparing for milk production, which can make your breasts feel swollen and sensitive.

• Digestive changes: Slower digestion (thanks to progesterone) can lead to bloating, heartburn, or constipation.

• Mood swings: Emotional ups and downs are very common and entirely normal.

"Your body is literally reprogramming itself to sustain another life. It’s exhausting—but also awe-inspiring."

2nd Trimester (Weeks 13–27): Growth and Stability

What’s happening:

• Visible baby bump: The uterus grows out of the pelvis, often leading to that celebrated “pop.”

• Increased energy: Many women feel more energized during this trimester.

• Back and pelvic pain: As your belly expands, your posture shifts. Hormones like relaxin loosen joints and ligaments to prepare for delivery - especially around the pelvis - sometimes leading to discomfort or instability.

• Skin changes: You may notice a dark line on your belly (linea nigra) or “pregnancy glow” from increased blood flow.

• Round ligament pain: Quick stretching of the ligaments supporting the uterus can cause sharp, brief pains on the sides of your belly.

  
  

3rd Trimester (Weeks 28–40): Preparing for Labor

What’s happening:

• Pressure in pelvis and bladder: Your growing uterus presses downward, increasing urinary urgency and pelvic heaviness.

• Swelling: Circulation slows slightly and fluid retention increases, especially in your legs, feet, and hands.

• Shortness of breath: As your uterus expands, it presses up against the diaphragm.

• Sleep challenges: Discomfort, frequent urination, and active baby movements may keep you up at night.

• Braxton Hicks contractions: These “practice contractions” help your uterus prepare for labor.

“Every ache and shift is your body rehearsing for the final act: birth.”

Whole-Body Transformations: More Than Just the Belly

• Pelvic floor changes: As the uterus grows and relaxin increases, the pelvic floor has to support more weight. This is why many pregnant people experience urinary leakage, pressure, or heaviness.

• Core function: The abdominal muscles stretch, sometimes separating slightly in a condition called diastasis recti. This is normal - and often resolves postpartum with proper care.

• Blood volume: It increases by nearly 50%! This supports both you and your growing baby but can cause increased heart rate or dizziness.

• Posture: You may notice a more pronounced curve in your lower back (lordosis) to balance the growing front load.

  
  

Tips to Support Your Changing Body

• Stay active: Gentle movement like walking, swimming, or prenatal yoga helps circulation, strength, and mood.

• Support your pelvis: Pelvic floor physical therapy during pregnancy can reduce discomfort and improve postpartum recovery.

• Hydrate and rest: Water and rest are your secret weapons during every stage of pregnancy.

• Wear supportive shoes and consider a belly band: These can help with back pain or pelvic pressure.

How Pelvic Floor Physical Therapy Can Help During Pregnancy

Pelvic floor physical therapy isn’t just for postpartum - it’s one of the best ways to support your body during pregnancy, too. A skilled pelvic floor therapist can:

• Relieve low back, hip, and pelvic pain

• Improve bladder control and reduce urinary leakage

• Teach safe core and pelvic floor exercises to prepare for labor

• Educate you on perineal massage, breathing techniques, and labor positions

• Help prevent or manage diastasis recti

• Set you up for an easier postpartum recovery

  
  

Whether you're experiencing symptoms or just want to feel more confident in your changing body, pelvic floor therapy is a proactive way to stay strong and supported.