Reaching week 27 of pregnancy means you are standing right at the threshold of the third trimester. For many expectant parents this is a reassuring milestone: your baby is becoming more active, more responsive and more recognisably ready for the world outside. Whether this is a settled stretch or one filled with fresh questions, understanding what is happening at 27 weeks pregnant can help you feel prepared and confident for the weeks ahead.
This week marks the close of the second trimester and the beginning of the final stretch of your pregnancy journey. It is a natural moment to take stock, to think about the appointments still to come, and to notice the many small changes in both your baby and your body. Building on where you were in week 26, here is what to expect.
Your baby at week 27
At 27 weeks, your baby is roughly the length of a large cauliflower, typically measuring around 36 to 37 centimetres from head to heel and weighing in the region of 900 grams to a kilogram. These figures are approximate and every baby grows at their own pace, so try not to worry if measurements differ from any average you read.
This is a period of remarkable development. Your baby's lungs are continuing to mature, producing a substance called surfactant that will help them breathe air after birth. Their brain is growing rapidly and forming new connections, and you may notice more distinct patterns of activity and rest as their sleep cycles become more established.
Around this stage many babies begin to open and close their eyes, and they can respond to light, sound and your voice. Some parents notice their baby reacting with a kick or a flutter to a familiar song or a loud noise. Regular hiccups, felt as small rhythmic movements, are also completely normal and nothing to be concerned about.
Your body at week 27
As your bump grows, you may notice a range of new sensations. Many people at 27 weeks pregnant experience back and hip ache, occasional shortness of breath as your uterus presses upwards, and mild swelling in the feet and ankles by the end of the day. Braxton Hicks contractions, the irregular practice tightenings of the womb, may also become more noticeable.
Other common and generally normal experiences this week include:
- Trouble sleeping, often helped by lying on your side with a pillow between your knees.
- Heartburn or indigestion, which tends to worsen as your baby takes up more space.
- Leg cramps, particularly at night.
- Stronger, more frequent fetal movements, which are a reassuring sign of your baby's wellbeing.
Getting to know your baby's individual pattern of movements is genuinely important from now on. There is no set number of movements to expect, but you should become familiar with what is normal for your baby. If you ever notice your baby's movements slowing down or changing, contact your midwife or maternity unit straight away, at any time of day or night, so they can check that all is well.
What to keep in mind this week
The third trimester is a good time to focus on rest, gentle movement and nourishing food. NHS guidance encourages a varied, balanced diet, staying hydrated, and keeping active in ways that feel comfortable, such as walking or antenatal exercise classes. Continuing your daily vitamin D, and folic acid if still advised, remains sensible, though you should confirm your own supplements with your midwife or GP.
This is also a natural point to start thinking ahead to labour and birth. Many parents find that learning practical coping techniques early helps them feel calmer as their due date approaches. Our calm birthing course is designed to build confidence and reduce anxiety around birth, giving you and your birth partner tools you can genuinely use on the day.
If you would like a clear overview of what still lies ahead, our pregnancy journey planner maps out your remaining scans, appointments and milestones in one personalised timeline.
Scans, tests and appointments
Several important NHS milestones cluster around this stage of pregnancy. If you have been offered a glucose tolerance test to check for gestational diabetes, this is typically carried out between 24 and 28 weeks, so it may fall around now. If you would like this assessed privately, our gestational diabetes (GTT) service can arrange it at a time that suits you.
The whooping cough (pertussis) vaccination is routinely offered from around 16 weeks up to 32 weeks, so if you have not yet had it there is still time to discuss it with your midwife or GP. In addition, the RSV vaccination is recommended from around 28 weeks to help protect your newborn, and your maternity team can advise on the timing that is right for you.
Week 27 can also be a valuable point to consider a detailed third-trimester assessment of your baby's growth and wellbeing. Our 3rd-trimester anomaly scan takes a careful look at your baby's anatomy, growth and the placenta at a later stage than the routine 20-week scan, offering additional reassurance during the final trimester. This is a private service and complements, rather than replaces, your NHS antenatal care.
Looking ahead to week 28
As you move into week 28, you will officially enter the third trimester, and your antenatal appointments will usually become more frequent. It is a moment to celebrate how far you and your baby have come, and to keep gently preparing for the weeks that remain.
Every pregnancy is different, and what matters most is that you feel supported and informed at each step. If anything feels unusual or you simply want reassurance, your midwife and maternity team are always there to help.
If you have concerns about your pregnancy or baby's wellbeing, contact your midwife, GP or maternity unit promptly.
This article is for general information only and is not a substitute for professional medical advice. Always speak to your midwife, GP or obstetrician about your own pregnancy.
