12 weeks pregnant

12 weeks pregnant is about 3 months. It falls in the third month of pregnancy. You are in week 12 of 40, in the first trimester. Here is what is happening with your baby and your body this week.

Your baby at 12 weeks

Reflexes are developing — the baby can curl its fingers and toes. The kidneys begin making urine.

Your baby's body is starting to catch up with the head, and the face looks more recognizably human, with the eyes moving closer together toward the front. Fingernails are beginning to grow, and the baby can now make spontaneous movements such as stretching, kicking, and turning, even though they are far too small for you to feel.

The brain is growing quickly, and the pituitary gland at its base has started making hormones. Bone marrow is beginning to produce white blood cells, an early step in building the immune system. The digestive system is practicing contractions, and the urine your baby's kidneys now make passes into the amniotic fluid.

Many of the main structures are now in place, so from here on much of your baby's development is about growth and maturing, rather than forming new organs.

Your body at 12 weeks

Your uterus is rising out of the pelvis, so you may need to urinate less often.

Your uterus is now about the size of a grapefruit, and your provider may be able to feel its top just above your pubic bone. Some people start to notice a small bump, especially in a second pregnancy, while others won't show for several more weeks. Rising blood volume and hormone changes can bring headaches and occasional dizziness. You may also notice early skin changes, such as darker patches on the face, sometimes called the mask of pregnancy, which usually fade after birth. Wearing sunscreen can help limit them.

Your belly at week 12

In month 3 (weeks 9–13) most people still don't look pregnant. Around 12 weeks the uterus rises out of the pelvis, and its top can be felt just above your pubic bone.

Belly size and shape vary a lot depending on your build, whether this is your first pregnancy, your baby's position and the amount of amniotic fluid. At checkups your doctor or midwife may measure your fundal height to track your baby's growth, and may arrange an ultrasound if the measurement is quite different from what they expect.

Symptoms at 12 weeks pregnant

• Less frequent urination than in earlier weeks
• Headaches
• Occasional dizziness
• Darker patches of skin on the face
• Lingering nausea or tiredness
• Increased vaginal discharge

Checkups around week 12

Week 12 is a common time for the first-trimester scan, which confirms your due date, checks how many babies there are, and often includes a nuchal translucency measurement as part of combined screening (usually offered between about 11 and 14 weeks). NIPT can also be done now if you haven't had it. Which tests are offered, and when, varies by country and clinic.

Common symptoms in the first trimester

The first trimester runs from week 1 to week 13. It is when your baby's major organs, spine and heart form, and when many people feel the most tired and nauseous. Not everyone has every symptom, and it is normal for symptoms to come and go. Common ones include:

• Nausea and vomiting (morning sickness), which can happen at any time of day
• Tiredness and needing more sleep
• Tender, swollen breasts
• Needing to urinate more often
• Food aversions or cravings and a metallic taste
• Mood swings
• Light spotting around implantation

Read the full first trimester guide.

When to call your doctor or midwife

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Frequently asked questions

How big is my baby at 12 weeks pregnant?

At 12 weeks pregnant, your baby is about the size of a lime. That is about 5.4 cm (2.1 in) from crown to rump, weighing about 14 g (0.5 oz).

How big is my belly at week 12 of pregnancy?

In month 3 (weeks 9–13) most people still don't look pregnant. Around 12 weeks the uterus rises out of the pelvis, and its top can be felt just above your pubic bone. Bump size, shape and when you start to show vary a lot from person to person.

Is it safe to tell people I'm pregnant at 12 weeks?

Many people share their news around 12 weeks because the chance of miscarriage has dropped considerably by now, and many have had a reassuring scan. There is no rule, though. Some people tell close friends and family earlier so they have support, while others wait longer. It's a personal choice, and you can share with different people at different times.

Is it normal not to have a bump at 12 weeks?

Yes. At 12 weeks your uterus is only just rising out of your pelvis, so many people, especially in a first pregnancy, don't have a visible bump yet. Any early tightness in your clothes is often due to bloating. When you start showing depends on your body shape, your muscle tone, and whether you've been pregnant before. Most people notice a bump sometime in the second trimester.

How accurate is the due date from the 12-week scan?

An ultrasound in the first trimester is considered the most accurate way to date a pregnancy, because babies grow at a similar rate at this stage. If the scan date differs noticeably from the date based on your last period, your provider may adjust your due date. Even so, only a small share of babies arrive on their exact due date, so think of it as an estimate.

What trimester is 12 weeks pregnant?

Week 12 is in the first trimester, which covers weeks 1 to 13.

How many months is 12 weeks pregnant?

12 weeks pregnant is about 3 months. It falls in the third month of pregnancy. The third month covers weeks 9 to 13. Pregnancy is about 40 weeks, or roughly 9 months, counted from the first day of your last period.

This page is general educational information and is not a substitute for advice from your doctor or midwife. Every pregnancy is different, and baby sizes are approximate averages. Last updated 2026-11-07. See our medical disclaimer.