Pregnancy Week 23

Evidence-informed content. Review status is maintained by the editorial team.

Week 23 sits within the second trimester. The lungs are developing structures needed for later breathing, though they remain immature. This guide explains what may be happening now, what can vary, and which concerns deserve prompt professional advice.

What is happening at pregnancy week 23

The uterus can press on the ribs, stomach and bladder as it rises. 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

Airway branches and lung cells continue maturing; hearing and startle responses become more developed.

Approximate size and growth

The fetus is around grapefruit sized and approximately 29 centimetres head to heel.

Changes you may notice

Breathlessness, reflux and stronger kicks may be noticeable. 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

• Mild exertional breathlessness
• Heartburn
• Rib or back discomfort

These experiences are possibilities, not a checklist. Symptoms can be mild, strong, intermittent or absent at week 23, and a different pattern does not automatically mean that anything is wrong.

Emotional wellbeing

Viability discussions can be emotionally charged. Individual outcomes depend on many clinical factors and should be discussed with specialists. 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

Choose iron-rich food regularly and report unusual fatigue, paleness, breathlessness at rest or a racing heart. 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 upright posture and breaks; new breathlessness at rest or chest pain requires urgent assessment. 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

Some people may have extra cervical, growth or specialist monitoring based on history.

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

Learn the signs and contact pathway for possible preterm labour without assuming they will occur.

• Keep urgent maternity contacts accessible
• Discuss anaemia screening timing
• Use supportive seating for rib comfort

Frequently asked questions

Could a baby survive if born at 23 weeks?

Survival and long-term outcomes vary greatly by exact gestation, health and specialist resources. A neonatal team can clarify local information sensitively.

Is breathlessness normal?

Mild exertional breathlessness can occur; sudden, severe or resting breathlessness, chest pain or faintness needs urgent care.

Should I compare my pregnancy with someone else at week 23?

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 23 in brief

Week 23 is important for lung development. Understand urgent pathways while treating each pregnancy’s outlook as individual.

References

The following authoritative resources support editorial and professional review. Guidance should be checked for currency and local applicability before publication.

• nhs.uk
• womenshealth.gov
• cdc.gov