12 weeks pregnant development

12 Weeks Pregnant: Symptoms and Baby Development

12 Weeks Pregnant: Your Baby’s Development

At 12 weeks pregnant, you’ve nearly reached the end of the first trimester, and your little one has been busy. All of your baby’s vital organs and body parts will be in place this week; even the sex organs have developed.

It’s still too early to determine the gender of your baby, but your healthcare provider will likely be able to let you know (if you choose to find out before birth) during an mid-pregnancy ultrasound scan in the second trimester. In the meantime, you can enjoy playing around with our Guess Your Baby’s Gender quiz.

Your baby’s heartbeat is probably audible with an external Doppler device by now, so you may get the opportunity to hear it if you have a checkup this week. At this time, your baby has fully formed eyelids. These aren’t just closed tightly; they’re actually fused together and will remain that way until late in your second trimester.

At this point, your baby's hands are a little more developed than the feet, and the arms are longer than the legs. The little nailbeds that recently developed are starting to sprout fingernails and toenails, which will continue to grow to the tips of the fingers and toes during the next trimester.

Your baby is also starting to move a little, but it’s still too early for you to feel these movements. During the coming weeks, your baby’s organs and muscles will continue to develop and your baby will continue to grow bigger.

The Size of the Fetus at 12 Weeks Pregnant

At 12 weeks, the fetus is about the size of a passion fruit, measuring close to 2.5 inches, crown to rump, and weighing approximately 0.5 ounce.

Take a look at the illustration below to get a visual idea of how your baby is developing:

Mom’s Body at 12 Weeks Pregnant

Feed me! As the nausea and discomfort of early pregnancy start to subside, you may find that you’re getting your appetite back. Be sure you're eating enough and maintaining a healthy diet, but don't feel you actually need to eat for two.

Experts recommend adding only about 300 extra calories a day, on average, during pregnancy. Your healthcare provider will be able to give you personalized advice about what’s right for you.

You might like to use our Pregnancy Weight Gain Calculator to get an idea of what a healthy weight gain looks like based on your pre-pregnancy weight.

You might be looking at your belly and wondering if it’s the right size for 12 weeks pregnant. Try not to compare your bump to other moms-to-be. Every pregnancy is unique and it will depend on many factors like your build, whether you’re pregnant with twins, your pre-pregnancy weight, and whether this is your first baby.

In other words, at 12 weeks pregnant, you may be starting to see a more prominent belly, but if not, don’t worry, it will appear before you know it. Read more on when you might start to show.

12 Weeks Pregnant: Your Symptoms

At 12 weeks pregnant, here are some of the symptoms you may be experiencing:

Bleeding and sensitive gums. As your blood volume increases and hormone levels change, you may find that your gums start to swell and are more sensitive; they may even bleed when you brush or floss. Although this can be disconcerting, it can be completely normal. Continue to brush and floss regularly, and speak to your dentist, if needed, to check that everything is OK. Using a softer toothbrush and rinsing with salt water (a teaspoon of salt dissolved into a cup of warm water) can be helpful.
Feeling lightheaded. During pregnancy, your body produces more blood vessels, and your hormone levels change. This can leave you feeling dizzy or lightheaded from time to time. Wearing loose clothing, keeping hydrated, avoiding long periods of standing, and remembering to eat regularly can help you feel better. Also, try to stand up slowly after sitting and avoid changing positions abruptly. Be sure to call your healthcare provider if you also have abdominal pain or vaginal bleeding, or if your feelings of lightheadedness persist.
Sensitivity to smells. Your sense of smell can be particularly sensitive during this phase of pregnancy. If certain odors bother you, try eating cold or room-temperature food to avoid strong odors, using a fan when cooking, and having someone else in your household take out the trash.
Bloating. Hormonal changes and your growing uterus might leave you feeling bloated. Eating slowly helps prevent you from swallowing air, and this may help relieve some of the bloating.
Spotting or bleeding. At 12 weeks pregnant, or anytime during pregnancy, if you notice bleeding other than light spotting (which can occur after sex, for example), especially if accompanied by cramping, it’s a good idea to contact your healthcare provider to get the symptom checked.

12 Weeks Pregnant: Things to Consider

Be sure to follow a balanced pregnancy diet that includes proteins like meat, chicken, fish, or plant-based substitutes. You’ll want to include a wide variety of vegetables and fruits each day for the vitamins and minerals they contain, plus calcium-rich foods like low-fat dairy, beans, nuts, and tofu.
Start doing Kegels, if you haven’t already. Kegel exercises help strengthen the pelvic floor muscles that support your uterus and bladder. There are many benefits, including helping to prevent accidental urination during and after your pregnancy. Kegels are easy to do: You simply squeeze your pelvic floor muscles by contracting those muscles you’d clench if you were trying to stop the flow of urine or stop yourself from passing gas. Hold for a few seconds, and then release. You should aim for at least 3 sets of 20 each day. You can increase how many Kegels you do and how long you hold them for as your muscles grow stronger. Consult our guide to learn more about Kegel exercises.
Start a pregnancy journal. You might want to write down all of your exciting pregnancy milestones so that you can look back on your journey after your baby is born. Consider taking weekly photos of your developing bump after it begins to show. Once you have an ultrasound scan, you could even add a print copy to the journal. There are many styles of pregnancy journals that you can buy online or from a local retailer, or you could create your own keepsake in the form of a scrapbook or even a traditional diary.
Have you started thinking about baby names yet? Try our Baby Name Generator, which will help you find a name you’ll love.
Think about how you’ll announce your pregnancy to colleagues. If you’re a working mom-to-be, you might be thinking of announcing your pregnancy early in the second trimester. Check out our tips on how to announce your pregnancy to coworkers.
Start a month-by-month baby bump photoshoot using our free downloadable bump to baby milestone cards. Whether you are showing or not yet, you can start taking a photo of your belly, holding one of our printed milestone cards. For added fun, you can also hold a fruit or vegetable that roughly matches the size of your baby. Your friends and family will love the resulting pictures, or you can simply keep them as a keepsake you can share with your child in the years to come.
Take stock of what’s to come. As you head toward the second trimester, find out what you need to know about this next stage of pregnancy in our handy go-to Pregnancy Guide.
If you have an ultrasound around this time and it shows that you are pregnant with not one baby but two (or more!), congratulations are in order! Having twins is amazing. Read on to learn about the difference between fraternal and identical twins and to find out about twin pregnancy week by week. And, if triple the fun is coming your way, read up on triplet pregnancy.

12 Weeks Pregnant: Ask Your Doctor

When and where will flu shots be available? Experts recommend all moms-to-be get the vaccine as soon as it comes out, which is usually a month or two before “flu season” begins. Flu season runs from October to May.
When is it OK to share the news with friends and colleagues?
Is it possible to avoid getting stretch marks?
Is chorionic villus sampling recommended?
Is a nuchal translucency ultrasound recommended?

12 Weeks Pregnant: Your Checklist

Start to plan when you will tell your employer about your pregnancy.
Plan how you will reveal your big news to family and friends. You could organize a fun pregnancy announcement party, or you could give those closest to you a special pregnancy announcement card. No matter how you do it, your loved ones will cherish this special moment.
Schedule a dental checkup.
Research local prenatal or birthing classes — your healthcare provider may be able to point you in the right direction. Find out when they start and when you need to sign up.
Sign up for even more pregnancy tips here:

You and Baby at 12 Weeks Pregnant

Key Takeaways at 12 Weeks Pregnant

Those overwhelming first-trimester symptoms may begin to wane. That means morning sickness may start fading soon and the outrageous exhaustion-fog may lift. Hope is on the horizon!
Have you bought maternity pants yet? If not, it’s time to loosen your purse strings—and your belt. Your belly is expanding and a budding bump is probably visible at this point.
Baby continues to develop by leaps and bounds every day. Their fingers and toes are no longer webbed, and their eyes, nose and fingernails are forming—so cool!
Getting a 12-week ultrasound? Your tech might be able to determine the sex of baby at this point, but it’s not guaranteed, nor is it foolproof.

Things are changing fast at 12 weeks pregnant. You’re reaching the home stretch of the first trimester (we know, finally!), which means your hormones are likely to tone things down a bit. It also means you may be ready to share your pregnancy news with family and friends. So exciting!

Baby at Week 12

Your 12-week fetus is almost done developing their body’s important systems and parts, which means it’s all about getting bigger and more mature from here on out. Yep, baby's about to enter the growth and maturation stage, in which organs and tissues will grow and develop rapidly.

Baby at 12 weeks is opening and closing their fingers and curling their toes, and their brain is developing fast!

Baby is now developing reflexes—if you poke your 12-week pregnant belly while looking at baby on an ultrasound, you'll likely see movement. If you’re 12 weeks pregnant with twins, your twosome is developing at a similar rate as singleton babies at 12 weeks. Later on, they’ll have a slightly slower rate of growth.

How big is baby at 12 weeks?

At 12 weeks pregnant, baby is as big as a plum. The average 12-week fetus is about 2.1 inches long and . 49 ounces. Now that baby's got pretty much all of their important organs, their main job is to keep on growing. Go, baby, go!

12 weeks pregnant is how many months?

At 12 weeks pregnant, you’re about three months pregnant. Remember, pregnancy is 40 weeks long, which doesn't break down cleanly into nine months. Just two more weeks until you can officially put your first trimester behind you!

12 week ultrasound

You may have one more prenatal checkup before the end of your first trimester. Whether or not you have a 12-week ultrasound may depend on your doctor’s preference and maybe also on what your insurance covers. If you do get an ultrasound at this time, you’ll notice that you can see your 12-week fetus more clearly this time around, which may make you want to start spreading the news that you’re expecting.

Itching to find out if it’s a boy or a girl? We hate to be the bearers of bad news, but on a 12 weeks pregnant ultrasound, the sex isn’t usually revealed. Between 12 and 13 weeks is the very earliest a boy or girl could possibly be seen on an ultrasound, and the anatomy is still difficult to make out with any certainty. Your OB or technician is much more likely to be able to see baby’s sex at the mid-pregnancy anatomy scan, which will happen around week 20. However, if you received DNA blood testing for chromosomal disorders, you may find out baby’s sex when you get those results—if you want to know, that is!

Around week 12, you might want to know more about baby’s health, so you may have genetic testing done to determine the risk of birth defects or other problems. This can be a little scary—and confusing—so be sure to ask your OB plenty of questions, and know that it’s much more likely that baby is a-okay than anything else.

What does a 12-week fetus look like?

With the first trimester almost done, you may be wondering, “what does a 12-week fetus look like?” New and exciting changes are happening for baby at 12 weeks! The eyes and nose take shape, fingers and toes lose their connective webbing, fingernails develop, teeth buds crop up and organs such as the kidneys and intestines keep growing.

3D Views: My Baby, My Body

See their progress for yourself with our 3D interactive tool.

See My Baby in 3D

See My Body in 3D

Pregnancy Symptoms at Week 12

Here’s the good news about 12 weeks pregnant symptoms: Morning sickness and fatigue may start to fade a bit soon as your hormones start to calm down. The bad? Headaches and dizziness may replace them. We’ll take that trade-off. Here’s more info about what’s happening to your body at 12 weeks pregnant:

Increased discharge

This clear discharge might seem weird, but it’s normal and has an important purpose: to protect your vagina from infection. But if you have yellow, greenish, pink or brown discharge during pregnancy week 12, call your doctor right away. Those colors could be a sign of infection or even miscarriage.

Spotting

Spotting or bleeding during pregnancy at 12 weeks could be worrisome—or it could be nothing at all. For example, your cervix is more sensitive during pregnancy, so simply having sex could cause light bleeding that’s harmless. If you’re spotting or bleeding, definitely tell your doctor. If the bleeding is accompanied by cramping or the flow is heavy, it’s an urgent call.

Headaches

These may start to intensify around week 12 of pregnancy. Headaches may be caused by hormonal shifts, drops in blood sugar, dehydration, lack of sleep or stress. To deal, pay attention to what might be triggering your headaches and try to avoid those culprits. If you notice a drastic increase in headaches or a type of headache you’ve never experienced before (such as a migraine), or if your headaches are accompanied by other weird symptoms, let your OB know.

Dizziness

Whoa! Hormone shifts and blood pressure changes could cause dizzy spells around pregnancy week 12 (and sometimes even earlier!). You can help prevent dizziness by snacking regularly, avoid becoming overheated and drinking plenty of water. Sit or lie down if you’re feeling dizzy or lightheaded and let your doctor know about any severe bouts.

If you’re 12 weeks pregnant with twins, you may still be experiencing morning sickness, while your singleton mom-to-be counterparts are likely starting to see the light at the end of the nausea tunnel. Know that things will likely improve soon.

What should I be feeling at 12 weeks pregnant?

Your body is working hard, and you may wonder, “what should I be feeling at 12 weeks pregnant?” You may not be showing much on the outside yet, but on the inside everything feels like it’s changing! In addition to typical 12 weeks pregnant symptoms, you may start to feel shifts with morning sickness and fatigue. One day you might be exhausted, and another you may feel a burst of energy, while nausea comes and goes. Hang tight—you're getting closer to the second trimester! Make sure you get plenty of fluids and healthy foods for those days when morning sickness makes it rough to keep anything down.

Your Pregnant Belly at 12 Weeks

At 12 weeks, your pregnant belly is probably getting noticeable now. This is one reason many moms-to-be start to tell others they’re expecting around 12 weeks. (Of course, if you’re 12 weeks pregnant with twins, you may have been showing for weeks now, obviously because you’ve got double the babies in there!)

If you haven’t already, start taking photos of your pregnant belly at 12 weeks. Trust us, after pregnancy you’ll want a memento of how much your body changed throughout.

How does your stomach feel at 12 weeks pregnant?

You may already feel the waistband of your clothes getting tighter as your stomach begins to round out. When baby is at 12 weeks, your uterus is expanding to make room for your growing little one. This can also cause a tight feeling in your stomach itself as the stretching uterus puts pressure on the surrounding tissues of your body. Gas or constipation are other common causes of tummy troubles.

“You are moving for two!… Going for a walk, doing your favorite workout or dancing to music, creates better weight management, cognitive development, cardiovascular health and beneficial health outcomes for baby. Remind yourself on your exhausted days that exercising through your pregnancy is going to make this journey easier for you and set your baby up for a lifetime of better health!” - Joanie Johnson Rubin, pre- and postnatal fitness expert and founder of Strong Mom Society

Tips for 12 Weeks Pregnant

Here’s some advice for living your best pregnant life as you finish up your first trimester and move into your second.

Give sore breasts some TLC

Your body’s hormones are getting you ready for breastfeeding, which can make breasts sore or tender. Soothe pain by wearing comfortable clothes that don’t irritate the body, trading in underwire bras for maternity or nursing bras with soft support or using ice packs for temporary relief.

Wear sun protection

One 12 weeks pregnant symptom that can occur for many women is melasma, or the “mask of pregnancy,” where dark spots appear on the face. It’s caused by those active hormones, but melasma can be made worse with sun exposure. Protect your skin with a mineral-based sunblock and a wide-brimmed hat, and stay in the shade or indoors during the day whenever possible.

Don’t give into junk food temptations

If your appetite starts to return as morning sickness fades, don’t feed it with lots of sugar, fats or processed foods. Healthy eating is good for you and baby, and it also helps you achieve a healthy weight gain moving forward. While it’s totally normal to not gain any weight in the first trimester (or even lose a few pounds), women of normal pre-pregnancy weight should plan on adding a pound or two a week during the second trimester

Think about getting physical

Pretty soon, you’ll have more energy, so make sure to talk with your OB about a safe exercise plan for the rest of your pregnancy. Regular workouts may help manage weight gain, make your heart and lungs strong, decrease pain and potentially reduce risk of issues such as gestational diabetes.

Pregnancy Checklist at 12 Weeks Pregnant

Reminders for the week:

save article

Week 11
Pregnancy

Week 13
Pregnancy

Get More From

Sign up for weekly updates to help you on the road to parenthood, and enter for a chance to win our $1000 new member sweepstakes!*

Choose Your Journey

Already a member? Log In

*See official rules

Watch These Videos Next:

Article saved.Go to My Saved Articles

Article removed.

12th week of pregnancy what happens to the fetus

Obstetric 12th week of pregnancy, which is counted from the first day of the last menstruation, is equal to the 10th week from the moment of conception. During this period, all the baby's systems are almost formed, nature is working on the details. This is the moment when the first trimester comes to an end. Any abnormalities in the development of the fetus are less likely. The baby is no longer so susceptible to the effects of external factors, the risk of early termination of pregnancy is behind.

What happens to the fetus?

At 12 weeks, the baby weighs an average of 15 g and is about 6 cm long. His body is still disproportionate - a large head and long limbs, but little fingers are covered with marigolds, and the eyes are not so widely spaced. In a tiny man, the upper layer of the epidermis is updated.

Interesting! The baby has facial expressions: he can close his eyes, wrinkle his nose, open his mouth.

There are other changes in the whole body:

The pituitary, thyroid and thymus produce hormones and cells for the immune system.
The liver produces bile and the kidneys excrete urine into the amniotic fluid.
The inside of the ear is forming, but the auricle itself is not yet formed, although the lobe may already be visible.
The intestine has moved to its proper place and is actively contracting
The heart is a complete organ: 4 chambers, 2 atria and ventricle. The frequency of contraction reaches up to 160 beats per minute.
Muscles begin to master movements.
The neck and larynx are being formed - the baby tries swallowing movements.
The skeleton is formed in the same way, but is still more represented by cartilaginous tissue.
The activity of the fetus is high - it moves the legs and arms, makes grasping movements.
The final stage of the formation of the respiratory system is also taking place. The baby's chest rises up and down, which is similar to the breathing cycle.

At the 12th week, a planned ultrasound is done, on which you can see the sex of the baby, but not always - the genitals are not yet fully formed. Diagnostics allows you to exclude fetal malformations, determine its size, find out the tone and parameters of the uterus of the expectant mother.

Important! At the 12th week, a woman will have to undergo a series of tests that are designed to detect genetic diseases. Such a survey is highly informative and safe.

What happens in the mother's body?

The function of producing progesterone, which was previously performed by the corpus luteum, is now transferred to the placenta. The uterus increases in size, but no longer presses on the bladder, so urination is less frequent than before. But the intestines feel pressure, hence constipation and flatulence appear.

It's time to change your usual clothes for more free and comfortable. It may seem to some mothers at the 12th week of pregnancy that they already feel the movement of their baby, but so far this is an illusion. Explicit tremors of tiny legs are yet to come.

Help! When choosing comfortable clothing, it is important to consider that it must be functional, made from natural hypoallergenic fabrics. A bra with wide straps is good, but softly supports the chest.

Rapid heartbeat, which is often observed in women, is associated with an increase in blood volume due to the fact that the fetus takes most of the oxygen and nutrients for its development. It can also increase blood pressure and cause anemia. During this period, hormonal changes sometimes lead to the formation of age spots on the body and face. But they will leave soon. Some women may begin to have problems with the condition of their hair and nails, while others, on the contrary, note improvements.

Weight gain must not exceed 3.5 kg, i.e. no more than 400 g per week. But it all depends on whether the expectant mother had excess weight before pregnancy. The mood and psychological state stabilizes somewhat, but the woman can still notice mood swings during the day. In addition, expectant mothers feel tired and overly sensitive.

12th week of pregnancy: sensations, size and development of the fetus

PrevNext

At present, all vital organs and channels of the nervous system have formed in the fetus. Bones that were soft until now begin to harden. The body of the child gradually straightens.

You almost made it! Now you are very close to the end of the first trimester, which many women find the most difficult. Now you can breathe a sigh of relief - enjoy it while you can. Soon, and right up to the birth of your baby, you will most likely feel that you cannot breathe freely. There is an explanation for this - your baby takes up more and more space inside, and there is no room left for your lungs.

It's time for shopping!

After the 12th week, persistent nausea and fatigue usually subside. You may find a return of appetite, and thoughts of food begin to seem more and more inviting. It is not uncommon for pregnant women to obsess over certain foods, sometimes foods that they never thought they wanted. Often it is not even the taste that matters, but the sensations when consuming the product. Ice crumbling on your teeth, crunchy raw vegetables, soft yogurt, toffee toffee - all this can cause an irresistible attraction. Stock up on your favorite foods - you'll be upset if they run out.

Physical changes at 12 weeks of gestation

The skin around your nipples may become darker, and age spots may appear on your face. Already now, a vertical dark line may form, running from the navel to the pubic region. This line occurs due to hormonal changes, after the birth of the child, it will disappear.
An increase in total blood volume can cause your skin to "glow" - you've probably heard of this effect of pregnancy. Those pesky pimples that have plagued you for the last few weeks are gone, leaving room for clear, healthy skin. Finally!
You no longer have to go to the toilet as often as before. From the 12th week, the uterus rises from the pelvis and stops pressing on the bladder. You can even feel this process happening, especially when you lie on the bed with a full bladder.

Emotional changes this week

From the 12th week you may feel more calm and relaxed. The risk of miscarriage is greatly reduced, and many couples feel that now is the right time to let others know that they are expecting a baby.
You may still be a little whiny and more sensitive than usual. Pushchairs, other pregnant women, babies, and even small furry animals can trigger a flood of tears. Turn off the TV if you feel like watching cute baby diaper commercials is too much for you right now.

Where are you dear?

One of the surprising changes in this period is that your partner begins to seem more sexually attractive to you. You hardly thought about bed fun lately, but now your libido has suddenly woken up and wants to take revenge. This is because energy has returned to you, and the genitals have received additional blood supply. Thanks estrogen!

It is perfectly safe to have sex throughout pregnancy, unless there is a risk of preterm labor or rupture of the membranes. In fact, many women say they have never felt more passionate, had a higher sex drive, or enjoyed sex more than they did during pregnancy. Some mothers-to-be fear that sex can cause injury or other harm to the baby. Do not worry: the baby is reliably protected by a thick mucous plug in the cervix, and the amniotic fluid acts as a buffer, damping shocks and concussions. The baby even has its eyes closed, at least until the 7th month.

What happens to the baby at the twelfth week of pregnancy

Your child has doubled in size in the last three weeks. Now, in size, it is approximately equal to a large ripe plum: its body length is about 5–6.5 cm.
Your child is constantly moving, kicking, stretching, twisting and turning. But it is still very small, and your uterus has just begun to rise, so for now you will not be able to feel its movements.
Your baby's bone marrow starts making its own white blood cells this week. These cells fight infection and help your baby stay healthy.
12-18 weeks is a critical period in your baby's brain development, so now you need to completely give up alcohol, tobacco and drugs. Also at this time, the pituitary gland of the baby begins to function and produce hormones.
By this time, the placenta is already doing all the important work - filtering oxygen and supplying nutrients for the growth and development of your baby.
Baby's eyelids completely cover the eyes, so they are well protected. And the baby may start sucking his thumb. It's cute, right?
The baby's intestines begin to contract and relax, exercising for healthy digestion. For the first feces of the baby, appearing a few hours after birth, there is a special word "meconium". But you won't see him soon.