12 Weeks Pregnant: What to Expect This Week
Week twelve is the finale of the first trimester — and for many couples, the week they've been waiting for to share their news. The 12-week scan is an emotional and exciting milestone.
Baby at Week 12: Size of a lime
Baby's Development at 12 Weeks
Reflexes are kicking in: if you could prod your belly, baby would wriggle in response. The digestive system is practising contractions and the intestines have moved from the umbilical cord back into the abdomen. The bone marrow is beginning to make white blood cells. The pituitary gland at the base of the brain is producing hormones. By the end of this week, all the major systems are in place — the remaining months are primarily about growth.
Your Body at 12 Weeks Pregnant
The end of the first trimester brings relief for many: nausea fades, energy begins to return, and the fog starts to lift. The uterus is now large enough to feel just above the pubic bone. Heightened libido is common in the second trimester as nausea fades and blood flow to the pelvic area increases. Continued bloating and constipation may persist for a few more weeks.
Tips for Week 12
- The 12-week scan is a great time to start sharing the news if that's your plan.
- Look into your workplace's maternity and paternity leave policies now — there may be deadlines to notify HR.
- Consider buying your first few pieces of maternity clothing — waistbands are about to get uncomfortable.
- If you haven't already, set up a shared space for your pregnancy journey — try Hello, baby to keep both partners in sync.
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Frequently Asked Questions
What does the 12-week scan look for?
The 12-week dating scan (also called the first-trimester scan) confirms the due date, checks that the baby has a heartbeat, looks at the basic anatomy, and measures the nuchal translucency. It can also detect some major structural abnormalities. Many parents get their first clear look at the baby's face and body at this scan.
Is it safe to travel in the first trimester?
For most healthy pregnancies, travel in the first trimester is safe. Long-haul flights carry a slightly increased risk of blood clots, so staying hydrated and wearing compression socks is advised. Check your travel insurance covers pregnancy complications, and always carry your maternity notes.
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