Third trimester · Week 33 of 40

Pregnancy week 33

Antibodies transfer; movements may feel sharper.

Approx. length43.7 cm
Approx. weight1918 g
Size feelpineapple
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Baby development at week 33

Immune antibodies pass more actively. The bones of the skull remain soft. Movements can feel jabby because space is tighter.

Average size estimates for week 33 are about 43.7 cm and 1918 g — roughly pineapple. Your ultrasound report and clinician’s dating override any website average.

What you might feel

Sleep interruptions increase. Nap without guilt when you can.

You are in the third trimester. Two pregnancies at the same week can feel completely different — treat these notes as orientation, not a checklist you must match.

Movements in week 33

By now, many clinicians encourage intentional awareness of fetal movement. Learn your baby’s usual active window, then use Preglo’s kick counter to log a calm session. Read how to count baby kicks if you want a simple method, or the 10-kick count overview. If movements feel clearly reduced, contact your care provider — see reduced fetal movement.

What to track this week

A calm next step in Preglo

Keep kick counts going; tighter space does not mean movement should disappear — patterns still matter.

Also useful: due date calculator · all weeks · Preglo features

Nearby weeks: Week 31 · Week 32 · Week 34 · Week 35

Educational averages only — not medical advice. Contact your clinician for symptoms that worry you, bleeding, severe pain, or reduced movements.

Week 33 FAQ

How big is the baby at week 33?

Typical educational averages are about 43.7 cm long and 1918 g. Individual growth and measurement methods vary.

Which trimester is week 33?

Week 33 is generally counted in the third trimester (weeks 1–12 first, 13–27 second, 28–40 third in common educational grouping).

Should I track anything special this week?

Keep kick counts going; tighter space does not mean movement should disappear — patterns still matter.

Preglo

Track this week in Preglo.

Week tracker, kick counter, water log, and widgets — private on iPhone.

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