27 weeks pregnant
Second trimester about 6 months
At 27 weeks pregnant, your baby is about the size of a cauliflower.
Baby this week
About 36cm. The brain is developing grooves and indentations that increase its surface area. The baby is increasingly aware of its environment and may startle at loud noises.
Did you know? The baby's brain develops folds and grooves (gyri and sulci) from around week 27, dramatically increasing its surface area and cognitive potential.
What she may be feeling
- Strong fetal movement
- Back pain
- Heartburn
- Braxton Hicks
- Swelling
- Fatigue
- Difficulty sleeping
- Shortness of breath
Tips for her this week
- You're entering the final stretch — acknowledge how far you've come.
- Sleep becomes more difficult from here as the belly grows — a pregnancy pillow helps enormously.
- Swelling, back pain, and Braxton Hicks will all likely increase.
- Start thinking about your postpartum mental health — it's important to plan for it.
For partners
- The third trimester starts next week — things accelerate from here.
- She may be feeling more anxious about birth as it gets closer — be a grounding presence.
- The hospital bag should be started this week at the latest.
- Research infant sleep safety: back sleeping, firm mattress, no loose bedding.
Partner to-do list
- Begin packing the hospital bag
- Research infant safe sleep guidelines
- Read about postpartum depression — it affects dads too
- Plan who is on call to drive to the hospital when labor begins
This week together
- Begin packing the hospital bag
- Discuss postpartum mental health openly
- Finalize visitor policy for after the birth
- Confirm your birth support team
When to call your doctor or midwife
Contact your care provider right away, or call emergency services, if she has:
- Decreased fetal movement
- Signs of preeclampsia
- Regular contractions before 37 weeks
- Heavy bleeding
- Severe heartburn that doesn't respond to treatment
Trusted guidance: NHS: Pregnancy · NHS: Pregnancy complications · ACOG: Pregnancy · Pregnancy Info: Your pregnancy
Common questions
How big is the baby at 27 weeks?
At 27 weeks pregnant, your baby is about the size of a cauliflower. About 36cm.
How many months is 27 weeks pregnant?
27 weeks pregnant is about 6 months, in the second trimester.
What can partners do at 27 weeks?
The third trimester starts next week — things accelerate from here. She may be feeling more anxious about birth as it gets closer — be a grounding presence.