you're 12 weeks pregnant.
last revised · baby is about 5.4 cm (2.1") · 14 g (0.49 oz)
At 12 weeks pregnant, your baby is about 5.4 cm and 14 g — End of the first trimester.
about the size of a…
End of the first trimester. Reflexes are kicking in — if you poke your belly, the baby will squirm in response.
this week's highlights
- End of first trimester
- Reflexes develop
- Vocal cords form
- Bone marrow makes white blood cells
how your baby looks
Fully formed in miniature — all organs are in place, fingers and toes have nails forming, and the face has eyes, ears, and a nose.
body in focus
- head
- Vocal cords are forming.
- body
- Bone marrow starts producing white blood cells.
- hands
- Reflexes work — fingers can curl into a fist.
- feet
- Reflexes work — toes can curl.
what's happening in your body
Your uterus has grown out of the pelvis and you may feel it just above the pubic bone. Many people see nausea fade this week.
symptoms at 12 weeks
- Nausea lifting
- This is the classic turning-point week — many people notice sickness fading noticeably from here. If it lingers, weeks 14 to 16 are the next common exit point.
- Energy returning
- As the placenta takes over hormone production, the bone-deep fatigue starts to lift. Enjoy the change, but let your body set the pace.
- Fewer loo trips, briefly
- As the uterus rises out of the pelvis it takes pressure off the bladder, buying you a few months of relative peace before the third trimester reverses it.
- Skin changes beginning
- Darkening of the nipples, a faint line down the belly, or patches of facial pigmentation can start appearing. All are hormonal, common and fade after birth.
- Mild headaches
- The hormonal handover around the end of the first trimester can trigger headaches. Hydration, regular meals and rest usually settle them; a severe headache with visual changes needs a call to your midwife or doctor.
- Occasional dizziness
- Blood pressure remains at its pregnancy low. Keep snacks handy and avoid standing still for long stretches.
gentle tips
- Eat enough calcium daily — your baby's bones are mineralizing.
- Consider sharing the news now that the first trimester is ending.
- Pelvic floor exercises (Kegels) help prepare for later pregnancy.
- Plan a healthcare check-in for the 12-week visit if not done.
- Apply sunscreen — your skin is more sun-sensitive now.
your week 12 checklist
- Have your dating scan and combined screening if planned
- Make your announcement plan real — many people share the news after this week's scan
- Photograph or scan your ultrasound pictures so they are backed up
- Review your budget for the months ahead: maternity pay dates, baby essentials, childcare research
- Start using sunscreen daily to limit pregnancy pigmentation (melasma)
what to expect next
Welcome to the second trimester — the easiest stretch for most. Energy lifts, nausea fades, and the belly starts showing.
common questions at week 12
How big is the baby at 12 weeks?
At 12 weeks, the baby measures about 5.4 cm and weighs approximately 14 g (5.4 cm (2.1") · 14 g (0.49 oz)).
What is developing at 12 weeks?
Fully formed in miniature — all organs are in place, fingers and toes have nails forming, and the face has eyes, ears, and a nose. Vocal cords are forming. Key milestones this week include: End of first trimester; Reflexes develop; Vocal cords form; Bone marrow makes white blood cells.
What symptoms are common at 12 weeks pregnant?
Your uterus has grown out of the pelvis and you may feel it just above the pubic bone. Many people see nausea fade this week.
What should I do at 12 weeks pregnant?
Welcome to the second trimester — the easiest stretch for most. Eat enough calcium daily — your baby's bones are mineralizing. Consider sharing the news now that the first trimester is ending. Pelvic floor exercises (Kegels) help prepare for later pregnancy.
Is 12 weeks really the safe point to announce a pregnancy?
By the end of week 12, miscarriage risk has fallen to a small fraction of its early-pregnancy level, which is why it is the traditional announcement point. But there is no rule — some people tell close friends early precisely so they would have support if something went wrong, and others wait until after the 20-week scan. The right time is whenever you both feel ready.
When will I start showing?
Most first pregnancies show a definite bump between 14 and 20 weeks, while second and later pregnancies often show from 12 weeks or earlier because abdominal muscles have stretched before. Height, torso length and core strength all shift the timeline. What you see at 12 weeks is usually bloat plus a rising uterus rather than the baby itself.
Can I find out the sex at the 12-week scan?
Sometimes a sonographer can make an educated guess from the angle of the genital tubercle, but it is not reliable and most clinics will not commit to it. NIPT blood testing can report sex accurately from around 10 weeks if you have opted for it. Otherwise, the 20-week anomaly scan is the standard point to find out — if you want to.
helpful tools
- Due Date Calculator
Find your estimated due date from your last period or conception date.
- Baby Names
Start exploring names — an early, joyful ritual.
Medically aligned with guidance from WHO, NHS and ACOG. How we write.