Pregnancy Week 39 vs Week 40

Complete comparison of baby development, mom's symptoms, and changes between these weeks

📊
Time Difference
1 week apart
🔄
Trimester
Both in 3rd trimester

Baby Size Comparison

Growth Progress

Week 39Mini watermelon
Week 40Small pumpkin
Your baby is approximately 99% through pregnancy

Week 39

📏
Length
19.9 inches
⚖️
Weight
7.3 pounds
🍎
Size Comparison
Mini watermelon

Week 40

📏
Length
20.2 inches
⚖️
Weight
7.6 pounds
🍎
Size Comparison
Small pumpkin

What Changes Between Week 39 and 40?

👶New Baby Developments

  • Baby is ready to meet you and fully prepared for life outside!
  • All organs are functioning perfectly
  • Baby has strong survival reflexes including sucking, rooting, and grasping
  • Coordination is fully developed
  • Baby is at complete development

🤰New or Changing Symptoms

  • Emotionally and physically ready to meet your baby
  • Possible increased contractions that may start and stop
  • Feeling anxious, impatient, or frustrated if not in labor yet
  • Labor could start at any time - today, tomorrow, or in 2 weeks
  • Extreme discomfort and difficulty with daily activities

📈Key Changes Summary

Baby Growth: Your baby continues to grow rapidly, with organs developing and maturing each day.
Your Body: Your body adapts to support your growing baby with various physical and hormonal changes.

Baby Development Milestones

Week 39 Development

  • Baby is continuing to gain weight and add final fat layers
  • Lungs are producing abundant surfactant for breathing
  • Baby's brain is still developing and will continue after birth
  • Antibodies from your placenta are supporting baby's immune system
  • Baby is fully ready to be born
  • Skin is smooth and pink

Week 40 Development

  • Baby is ready to meet you and fully prepared for life outside!
  • All organs are functioning perfectly
  • Baby has strong survival reflexes including sucking, rooting, and grasping
  • Coordination is fully developed
  • Baby is at complete development
  • Baby will continue gaining weight if they stay in longer

Common Symptoms

Week 39 Symptoms

  • Lightning crotch pains - sharp shooting pains in pelvis and vagina
  • Increased contractions that may be irregular or regular
  • Possible water breaking (spontaneous rupture of membranes)
  • Intense anticipation, anxiety, and impatience
  • Extreme physical discomfort
  • Possible burst of energy (nesting)

Week 40 Symptoms

  • Emotionally and physically ready to meet your baby
  • Possible increased contractions that may start and stop
  • Feeling anxious, impatient, or frustrated if not in labor yet
  • Labor could start at any time - today, tomorrow, or in 2 weeks
  • Extreme discomfort and difficulty with daily activities
  • Possible signs of labor beginning

Nutrition Tips

Week 39 Nutrition

  • Eat light, easily digestible meals
  • Stay hydrated with water and avoid dehydration
  • Avoid large, heavy meals that could cause nausea during labor
  • Keep high-energy snacks like granola bars, bananas, and honey readily available
  • Eat smaller portions more frequently
  • Include protein for sustained energy

Week 40 Nutrition

  • Stay well hydrated with water throughout the day
  • Eat light, healthy, balanced meals
  • Keep energy-boosting foods readily available for early labor
  • Avoid overeating which could cause nausea during labor
  • Include foods rich in protein and complex carbs
  • Eat regularly to maintain energy

⚕️When to Contact Your Healthcare Provider

During weeks 39 to 40, contact your healthcare provider if you experience:

  • Severe abdominal pain or cramping
  • Heavy bleeding or passing clots
  • Severe headache with vision changes
  • Persistent fever over 100.4°F (38°C)
  • Sudden swelling of hands, face, or feet
  • Decreased fetal movement

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