Week 31 of Pregnancy
Third trimester
For informational purposes only. This page is not medical advice. Every pregnancy is different — always consult your doctor, midwife, or healthcare provider for guidance specific to your situation. In an emergency, call your provider or 911 immediately.
Baby is
about the size of a coconut
16.2 inches · 3.3 lbs
Baby this week
- •Brain development accelerates with more neural connections forming
- •Lungs continue maturing and producing surfactant (crucial for breathing after birth)
- •Baby can regulate their own body temperature
- •Pupil dilation reflex is now in place
You this week
- •Increased Braxton-Hicks contractions as uterus prepares
- •Shortness of breath due to baby's growth and diaphragm pressure
- •Swelling in feet and ankles, especially by day's end
- •Lower back pain from shifting weight and posture changes
- •Difficulty sleeping despite fatigue
This week's tips
- •Practice pelvic floor exercises (Kegels) daily to strengthen muscles for labor and recovery
- •Elevate your feet when sitting to reduce swelling; aim for 2-3 times daily
- •Sleep on your left side to optimize blood flow and reduce pressure on your liver
- •Stay hydrated—thirst increases in the third trimester
- •Discuss birth plan preferences and pain management options with your healthcare provider now
Informational only — always check with your doctor or midwife for advice specific to you and your baby.
Looking ahead
You're entering the home stretch! Over the next few weeks, your baby will gain about a pound each week as they prepare for birth. Your own body is gearing up too—keep communication open with your care team about any concerns.
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For informational purposes only. This page is not medical advice. Every pregnancy is different — always consult your doctor, midwife, or healthcare provider for guidance specific to your situation. In an emergency, call your provider or 911 immediately.
This content is for informational purposes only and is not medical advice. Every pregnancy and baby is different. Always consult your doctor, midwife, or pediatrician for guidance specific to your situation.
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