How many months is 12 weeks pregnant?

12 weeks pregnant puts you in month 3 of pregnancy. Month 3 covers weeks 9 to 13. Providers count in weeks; months are approximate.

How big is the baby at 12 weeks?

At 12 weeks, the baby is about the size of a lime, roughly 5.4 cm long and around 14 g. That is an average; healthy babies vary.

Are you considered safe at 12 weeks pregnant?

The risk of miscarriage is much lower by 12 weeks. Most miscarriages happen before 13 weeks, and once a scan has shown a heartbeat the risk falls week by week. In one study of women with no symptoms, it was under 1% for those seen at 9 or 10 weeks. That's why many people share their news after the 12-week scan. Later losses are rare but can happen, so keep going to checkups and call about bleeding, fluid leaking, or severe pain.

What does a baby look like at 12 weeks?

At 12 weeks the baby looks like a small, recognisable baby: a large head, a face with a nose and chin you can see in profile, arms and legs that bend, and separate fingers and toes. The skeleton is still soft and is starting to harden into bone. On the scan you may see it kick, stretch or turn, though you won't feel any of this for weeks yet.

Is cramping normal at 12 weeks pregnant?

Mild aches and twinges low in the belly are common as the uterus grows up out of the pelvis and the ligaments that hold it soften and stretch. They should be mild and ease with rest. Call your provider about cramps that are strong or come in waves, or that come with bleeding, fever, or pain when you pee.

Is spotting at 12 weeks pregnant normal?

Light spotting can still happen at 12 weeks, for example after sex or an internal exam, because the cervix has a richer blood supply in pregnancy. It is less common than in weeks 5 to 8, so mention any bleeding to your provider. Get checked the same day if the bleeding is heavy or bright red, or comes with cramps.

12 Weeks Pregnant

At 12 weeks pregnant, you're nearly at the end of the first trimester. Your baby is about 5.4 cm long from head to bottom, around the size of a lime, and all the main body parts are in place. From here on, the work is mostly growth. For many people this is the week of the first big scan, which checks your dates and can include screening for Down syndrome. The placenta has taken over feeding the baby, and some people start to feel less sick, although for most, nausea clears up by weeks 16 to 20. This page covers what the 12-week ultrasound shows, whether you'll have a bump yet, and how safe 12 weeks really is.

What trimester is 12 weeks?

Week 12 is in the first trimester, which runs from week 1 to week 12. The second trimester starts at week 13, 1 week from now.

Week 12 — first trimester, month 3; 28 weeks to go until your due date.
Baby's size — about a lime, ~5.4 cm.

Not sure it's 12 weeks? Try our due date calculator.

★ Last week of the first trimester; miscarriage risk drops notably.

How big is your baby at 12 weeks?

Size of a

lime

Length, head to bottom

~5.4 cm

Weight

~14 g

Up from a fig last week to a lime now.

Baby development at week 12

Most major structures are now formed, and the rest of pregnancy is largely about growth and maturation. The skeleton, still made of soft tissue, is starting to harden into bone. The sex organs have formed, although most scans can't tell the sex yet. The placenta has taken over feeding the baby from the yolk sac, and reflexes are developing — the fingers can curl. About the size of a lime.

What an ultrasound shows at 12 weeks

The 12-week scan is usually done over your belly. It measures the baby from head to bottom to confirm your due date, checks the heartbeat, and shows how many babies there are. You can often see the baby's profile, arms and legs, and it may be moving. If you're having twins, this is the best time to check whether they share a placenta, which decides how often you'll be scanned later.

If you choose screening, the scan can include a nuchal translucency measurement. This measures the fluid at the back of the baby's neck, and it can only be done between 11 and 14 weeks. Combined with a blood test, it estimates the chance of Down syndrome and some other conditions. It gives a chance, not a diagnosis: a scan alone can't show that a baby has Down syndrome, and a result can only be confirmed with CVS or amniocentesis.

Most 12-week scans can't show the baby's sex. The sex organs have formed, but they usually can't be told apart on a scan until later.

Your body at 12 weeks

Morning sickness easing for most
A small baby bump may start to show
Less frequent urination as the uterus rises out of the pelvis
Visible skin changes like a darker line down the belly (linea nigra)

Your belly at 12 weeks

Around 12 weeks, the top of the uterus reaches the level of your pubic bone, so this is when some people first notice a small curve low down. In a first pregnancy, much of what shows at 12 weeks is still bloating and a thicker waist, so clothes feel tight before a true bump appears.

If you've been pregnant before, you'll often show earlier, and twins show sooner too. As the uterus rises out of the pelvis, it presses less on your bladder, so some people need to pee a little less often.

Tips for week 12

The 12-week scan (dating/nuchal translucency) typically happens now
Many people choose to share their news after this scan
Keep moving — approved exercise supports energy and circulation

12 Weeks Pregnant: your questions

What trimester is 12 weeks?: Week 12 is in the first trimester, which runs from week 1 to week 12. The second trimester starts at week 13, 1 week from now.
How many months is 12 weeks pregnant?: 12 weeks pregnant puts you in month 3 of pregnancy. Month 3 covers weeks 9 to 13. Providers count in weeks; months are approximate.
How big is the baby at 12 weeks?: At 12 weeks, the baby is about the size of a lime, roughly 5.4 cm long and around 14 g. That is an average; healthy babies vary.
Are you considered safe at 12 weeks pregnant?: The risk of miscarriage is much lower by 12 weeks. Most miscarriages happen before 13 weeks, and once a scan has shown a heartbeat the risk falls week by week. In one study of women with no symptoms, it was under 1% for those seen at 9 or 10 weeks. That's why many people share their news after the 12-week scan. Later losses are rare but can happen, so keep going to checkups and call about bleeding, fluid leaking, or severe pain.
What does a baby look like at 12 weeks?: At 12 weeks the baby looks like a small, recognisable baby: a large head, a face with a nose and chin you can see in profile, arms and legs that bend, and separate fingers and toes. The skeleton is still soft and is starting to harden into bone. On the scan you may see it kick, stretch or turn, though you won't feel any of this for weeks yet.
Is cramping normal at 12 weeks pregnant?: Mild aches and twinges low in the belly are common as the uterus grows up out of the pelvis and the ligaments that hold it soften and stretch. They should be mild and ease with rest. Call your provider about cramps that are strong or come in waves, or that come with bleeding, fever, or pain when you pee.
Is spotting at 12 weeks pregnant normal?: Light spotting can still happen at 12 weeks, for example after sex or an internal exam, because the cervix has a richer blood supply in pregnancy. It is less common than in weeks 5 to 8, so mention any bleeding to your provider. Get checked the same day if the bleeding is heavy or bright red, or comes with cramps.

Useful at week 12

Pregnancy weeks to months — 12 weeks is month 3 — see every week
Pregnancy due date calculator — compare your period-based date with the scan
hCG levels and twins — what the numbers can and can't tell you
Pregnancy discharge by trimester — what changes after the first trimester
Exercise in pregnancy — staying active into the second trimester

← All weeks: the full pregnancy week-by-week guide

Sources

Checked against the following public guidance on October 2, 2026. Advice can differ between countries; your doctor, nurse or midwife can apply it to you.