Week 27: Third Trimester Begins - Final Preparations

Reviewed by: HiMommy Expert Board
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5 min read
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Jul 8, 2025
Table of contents
Welcome to the Home Stretch
Week 27 marks the official beginning of your third and final trimester – the home stretch of your pregnancy journey! This milestone brings mixed emotions: excitement about meeting your baby soon, but also awareness that the physical challenges of late pregnancy are beginning. The third trimester is characterized by rapid fetal growth, maternal body changes, and increasing anticipation.
With approximately 13 weeks remaining until your due date, this is an excellent time to begin thinking about final preparations for your baby's arrival, including nursery setup, birth plan discussions, and practical preparations for postpartum life.
Dramatic Fetal Growth Period
The third trimester is primarily focused on growth and weight gain. Your baby will approximately triple their weight over the next 13 weeks, growing from about 800 grams now to roughly 3,200-3,600 grams at term. This rapid weight gain is crucial for temperature regulation, energy storage, and overall survival after birth.
The growth isn't just about weight – your baby's length will increase significantly, and all organ systems will continue maturing. The brain, in particular, will undergo tremendous development during these final weeks, with rapid myelination and neural connection formation.
Lung Development Continues
While your baby's lungs have been developing throughout pregnancy, the third trimester brings crucial final maturation. Surfactant production continues to increase, and the alveoli (air sacs) become more numerous and efficient. Each week that passes significantly improves your baby's ability to breathe independently if early delivery occurs.
The lungs are practicing breathing movements more regularly now, helping to strengthen the diaphragm and other respiratory muscles. These practice breaths also help circulate amniotic fluid, which is important for continued lung development.
Nervous System Maturation
Your baby's nervous system is becoming increasingly sophisticated. The brain is developing rapidly, with new neural connections forming constantly. The process of myelination (coating nerve fibers with a protective substance) accelerates during the third trimester, improving the speed and efficiency of nerve signal transmission.
Reflexes are becoming more coordinated and pronounced. Your baby's movements are becoming more purposeful and less random, indicating improved neural control over muscle function.
Your Changing Body in the Third Trimester
As you enter the third trimester, you may begin experiencing new physical changes:
- Increased shortness of breath as your growing uterus puts pressure on your diaphragm
- Heartburn and indigestion as stomach space decreases
- Back pain and pelvic pressure as your baby grows larger
- Difficulty sleeping due to size and discomfort
- Braxton Hicks contractions as your uterus prepares for labor
- Swelling in hands, feet, and ankles due to increased fluid retention
Emotional Preparations
The third trimester often brings a shift in emotional focus from the wonder of pregnancy to the reality of impending parenthood. It's normal to feel:
- Excitement about meeting your baby
- Anxiety about labor and delivery
- Concerns about your ability to be a good parent
- Nesting instincts and desire to prepare
- Impatience as the weeks progress
Recipe: Energy-Sustaining Lentil Curry
Ingredients
- 1 cup red lentils, rinsed
- 1 can coconut milk (light)
- 1 cup vegetable broth
- 1 onion, diced
- 2 cloves garlic, minced
- 1 tbsp fresh ginger, grated
- 1 tbsp curry powder
- 1 tsp turmeric
- 1 cup spinach, chopped
- 2 tbsp olive oil
- Salt to taste
Instructions
- Heat oil in large pot, sauté onion until softened
- Add garlic, ginger, and spices, cook for 1 minute
- Add lentils, coconut milk, and broth
- Simmer for 20 minutes until lentils are tender
- Stir in spinach and cook until wilted
- High in protein and iron for third trimester energy needs
Sources:
- Committee on Obstetric Practice. (2017). “Definition of term pregnancy”
- Jobe, A.H., et al. (2001). “Pulmonary surfactant therapy”