Pregnancy › Week by Week › Week 27
At 27 weeks your baby is about the size of a cauliflower, and this is the final week of your second trimester before the home stretch begins.
Size
A cauliflower
head to heel
Length
14.4 in
about 36.6 cm
Weight
1.9 lb
about 875 g
Your baby at 27 weeks
The brain is more active than ever with sleep and wake cycles, and you may start to feel the rhythmic little jumps of hiccups.
This closing week of the second trimester is all about the brain and the routines that come with it. Your baby is behaving more and more like a newborn, settling into cycles of rest and activity and even getting the hiccups.
Brain. Brain tissue and activity are increasing quickly, and your baby now moves through sleep and wake cycles, including phases that look like dreaming sleep. These patterns will keep developing all the way to birth.
Hiccups. Many people start to feel hiccups around now, a series of small, rhythmic jumps that are quite different from kicks. They are harmless and a sign the diaphragm is getting practice, and they can come and go several times a day.
Eyes and lungs. Your baby opens and closes the eyes and can react to light. The lungs are still immature but developing steadily, adding the surfactant and structure they will need over the weeks ahead.
How big is your baby at 27 weeks?
About 14.4 inches (36.6 cm) head to heel and around 1.9 pounds (875 g).
Your baby is measured head to heel now that the legs are extended. These are averages, so your baby may weigh a little more or less, and your provider follows your baby’s own growth curve over time.
Your body at 27 weeks
Movements are strong and frequent as you close out the second trimester, with heartburn, cramps, and shorter nights all part of the picture.
You will likely feel plenty of movement now, from firm kicks to those funny little hiccups, and it is a good point to start noticing your baby’s daily pattern, which is reassuring. Common company this week includes heartburn, swelling in the feet and ankles, leg cramps that can strike at night, and sleep that is harder to find as the bump grows.
One thing worth asking about: magnesium in the evening. Some people find it settles night time leg cramps and makes sleep easier, though the evidence is mixed. Check with your doctor or midwife before starting magnesium or any supplement in pregnancy.
Side sleeping with a pregnancy pillow and a little gentle stretching before bed can ease both cramps and restlessness. With the third trimester about to begin, this is a natural moment to start a loose list of newborn essentials or a registry, at whatever pace feels good, so the early weeks with your baby feel a bit more prepared.
What is normal, and when to call your provider
Strong movement and everyday aches are normal, but call your doctor or midwife the same day if you have any of these:
- Heavy bleeding, or any bleeding with pain
- Severe or persistent abdominal pain, or regular tightenings that grow closer together and do not ease
- A fever over 100.4°F (38°C)
- A severe headache with vision changes, or sudden swelling of the face and hands, which can be signs of pre-eclampsia
- Fluid leaking or a gush from the vagina
- Pain or burning when you urinate
- A noticeable drop in your baby’s usual movement once you have come to know its pattern
Your week 27 checklist
- Keep taking your prenatal vitamin every day
- Notice your baby’s movement and hiccup patterns, they are reassuring signs
- Ease leg cramps with hydration, gentle stretching, and a pregnancy pillow
- Start a relaxed list of newborn essentials or a registry, and finalize your leave plan
- Read ahead about the third trimester so you know what is coming
Appointments and tests around 27 weeks
This is the last stop in the second trimester, and your visits are about to become more frequent.
At your checkup your provider will check your blood pressure and weight, measure your fundal height to track your baby’s growth, and listen to the heartbeat. If your glucose screening has not happened yet, it will usually be wrapped up by 28 weeks, and if you are Rh negative your provider may discuss an injection around this time. From the third trimester onward, prenatal visits generally move to every two weeks, then weekly near the end. You can read what lies ahead in our 28 weeks guide and the full third trimester guide.
A few things worth having on hand now
A note for your partner
Feel for hiccups this week, a series of tiny, rhythmic jumps that are different from kicks. It is a sweet, funny thing to share. This is also a great time to sit down together and start a loose registry, so the practical prep becomes something you do as a team rather than a solo to do list.
You are not alone this week
Closing out the second trimester can bring a mix of pride and nerves, the finish line feels closer, and there is still plenty ahead. If you are tired and a little achy, you are in very normal company. Take the third trimester one week at a time, lean on your support, and let yourself look forward to meeting your baby.
27 weeks pregnant, common questions
Is 27 weeks the end of the second trimester?
Yes. Week 27 is generally counted as the last week of the second trimester, with the third trimester beginning around week 28. You are two thirds of the way through, and the final stretch is just ahead. Our third trimester guide walks through what to expect.
What do baby hiccups feel like?
Hiccups feel like a series of small, rhythmic, evenly spaced jumps or twitches, quite different from the bigger, less regular movement of kicks. They are completely harmless, a sign your baby’s diaphragm is practicing, and they can happen several times a day.
Should I start counting my baby’s movements?
By now it helps to be familiar with your baby’s usual pattern of activity and rest. Formal kick counting is generally a third trimester habit, and your provider can tell you when and how to start. In the meantime, if you notice a clear drop from what is normal for you, call the same day.
Is it too early to start a baby registry?
Not at all. The end of the second trimester is a comfortable, low pressure time to begin a registry while you still have energy. Starting with a short list of newborn essentials keeps it manageable, and you can add to it at your own pace.
Sources
- American College of Obstetricians and Gynecologists (ACOG), second and third trimester care guidance.
- Mayo Clinic, Fetal development: the 2nd trimester, and Prenatal care in the third trimester.
- MedlinePlus, National Library of Medicine (NIH), Fetal development and prenatal care.
Medical disclaimer: This page is for information and education only and is not a substitute for professional medical advice. Every pregnancy is different. Always follow the guidance of your doctor, midwife, or qualified provider, and contact them with any concerns.