27 Weeks Pregnant: What to Expect This Week
Twenty-seven weeks pregnant — the final week of the second trimester. Your baby may have started sucking their thumb, and can now distinguish between different voices. The third trimester is just one week away.
Baby at Week 27: Size of a cauliflower
Baby's Development at 27 Weeks
Brain development is accelerating dramatically. Baby can distinguish between different voices and is thought to prefer familiar ones, particularly the primary caregiver's. Thumb-sucking, a self-soothing behaviour, may begin this week. The lungs are more developed, and survival rates outside the womb at this gestational age are above 85% with intensive care. Baby is gaining weight rapidly as fat stores build.
Your Body at 27 Weeks Pregnant
Leg cramps, especially at night, are very common in the second and third trimester — magnesium supplements are often recommended. Heartburn and reflux are nearly universal by now. Back and hip pain from shifting pelvic joints. The belly may feel very tight and itchy. Shortness of breath begins for some as the uterus reaches toward the diaphragm.
Tips for Week 27
- Magnesium glycinate (check dose with your provider) can help with leg cramps and improve sleep.
- Start thinking about your maternity leave start date and when to notify your employer formally.
- Review your birth plan draft with your provider at your next appointment.
- Pre-register at your delivery hospital if this option is available — it reduces paperwork on the day.
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Frequently Asked Questions
What are Braxton Hicks contractions?
Braxton Hicks are irregular, painless tightenings of the uterus that most people notice from the second trimester, becoming more frequent in the third. They're the uterus "practising" for labour. Unlike real contractions, they don't increase in intensity or regularity and usually ease with rest, hydration, or changing position. If you experience regular, painful contractions before 37 weeks, always contact your provider.
What should I pack in my hospital bag?
Hospital bag essentials include: maternity notes, birth plan, comfortable loose clothing, going-home outfit for baby (with a cardigan), nappies and wipes, feeding supplies (nursing bra/breast pads or formula), toiletries, snacks, phone charger, and a car seat for the journey home. A full packing list is available on our blog.
Get your kick counter ready
Hello, baby's kick counter is built for the third trimester — tap once per movement and your partner sees results in real time.
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