Evidence-informed content. Review status is maintained by the editorial team.
Week 31 sits within the third trimester. Brain connections expand rapidly and the fetus continues gaining fat and muscle. This guide explains what may be happening now, what can vary, and which concerns deserve prompt professional advice.
What is happening at pregnancy week 31
The uterus may make bending, sleeping and prolonged positions less comfortable. Gestational age is counted from the first day of the last menstrual period, so early numbered weeks include time before conception. Dating may later be adjusted using clinical information and ultrasound.
Baby development
The senses are increasingly integrated, pupils respond to light and the nervous system coordinates body functions more effectively.
Approximate size and growth
The fetus is roughly coconut sized, commonly about 41 centimetres head to heel.
Changes you may notice
Movements can feel like rolls and stretches rather than only kicks. Some people notice several changes at once, while others feel little different. The presence or absence of a symptom cannot on its own confirm how a pregnancy is progressing.
Common symptoms
- Strong rolling movement
- Interrupted sleep
- Breathlessness, reflux or backache
These experiences are possibilities, not a checklist. Symptoms can be mild, strong, intermittent or absent at week 31, and a different pattern does not automatically mean that anything is wrong.
Emotional wellbeing
Feeling both ready and unready is normal. Rehearse how to ask questions and request time for decisions during care. A short daily check-in can help: notice what feels manageable, identify one source of support, and write down a concern instead of carrying it alone.
If worry is persistent, interferes with sleep or daily life, or makes it hard to cope, tell your midwife, doctor or another trusted healthcare professional. Emotional health deserves the same attention as physical health.
Nutrition and hydration
Focus on regular intake and hydration; report inability to eat or drink adequately. Sip fluids regularly and use urine colour and thirst as everyday prompts, while following any fluid advice given for a medical condition.
Aim for regular meals built around vegetables and fruit, wholegrain or other fibre-rich foods, protein foods and suitable dairy or alternatives. Follow local advice on prenatal supplements and foods to avoid; individual needs differ, especially with allergies, diabetes, anaemia or severe nausea.
Safe movement and daily comfort
Use shorter activity periods with more rest and stable support. Choose an intensity at which you can still speak comfortably, include rest, and adapt for heat, balance changes or pelvic discomfort.
For an uncomplicated pregnancy, comfortable everyday activity is often encouraged. Stop and seek advice if movement causes pain, bleeding, dizziness, chest symptoms, fluid loss or contractions. A clinician can tailor advice for complications or a previously inactive routine.
Appointments and screening
Review fetal growth, position as relevant, blood pressure and symptoms; additional scans are based on clinical indication.
Exact schedules and tests vary by country, pregnancy history and care plan. Keep a note of new symptoms, medicines and questions so your appointment can focus on what matters to you.
Warning signs and when to seek care
Trust a strong sense that something is wrong: maternity services would rather assess a concern than have you delay because it does not match a list.
- Contact your maternity service promptly for vaginal bleeding, suspected fluid loss, severe or persistent abdominal pain, a severe headache, vision changes, sudden swelling, fever, breathing difficulty, chest pain or feeling acutely unwell.
- Once you have established a usual pattern of movement, seek maternity advice promptly if your baby is moving less than usual or the pattern changes. Do not wait for the next day.
- Use emergency services for collapse, severe breathing difficulty, heavy bleeding, a seizure or another immediately life-threatening concern.
Practical preparation for this week
Plan who will communicate updates and care for dependants if labour begins.
- Confirm a support-person plan
- Pack essential documents gradually
- Discuss consent and communication preferences
Frequently asked questions
Why do movements feel different?
As space changes, rolls and stretches may replace sharp kicks, but frequency should not simply decline. Report a changed pattern.
Is a growth scan routine?
That depends on local practice and risk factors. Fundal measurements or clinical history may lead to ultrasound assessment.
Should I compare my pregnancy with someone else at week 31?
No two pregnancies follow an identical pattern. Dating can vary, symptoms are influenced by many factors, and growth is assessed over time rather than from a single comparison. Bring personal concerns to your maternity team.
Week 31 in brief
Week 31 features rapid brain maturation and changing movement quality. Communication and practical support plans can reduce pressure.
References
The following authoritative resources support editorial and professional review. Guidance should be checked for currency and local applicability before publication.
OUR REVIEW PROMISE
Evidence-based, clearly reviewed.
Healthier Baby Today articles are reviewed for accuracy and updated as guidance changes.
Last updated: July 17, 2026
