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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.

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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:

Pregnancy calendar 12 weeks - Miracle Doctor multidisciplinary clinic in Moscow

The twelfth week sums up the first trimester of pregnancy. The laying of all organs has already been completed in the fetus; after 12 weeks, their further growth and development takes place. At the beginning of the week, the size of the fetus from the crown to the coccyx is 5.3 centimeters, weight is about 10-12 grams. From the 12th week, the growth rate of the child accelerates, on average, the KTP indicator (coccygeal-parietal size) increases by 1.5-2 mm per day. By the end of the week, the growth of the fetus is 6.1 cm, and the weight is 14 grams. It is comparable in size to a large chicken egg. The amount of amniotic fluid surrounding the fetus is about 50 ml. nine0003

This week, the baby's first reflexes appear. He has learned to squint, can open his mouth and begins to move his fingers and toes. The fingers of the fetus are already divided, they have marigolds, the interdigital membrane is absent. This week, active ossification of the fetal skeleton begins. Until now, its basis was cartilaginous tissues, which are gradually beginning to be replaced by bone tissues.

During the 12th week of pregnancy, there is an improvement in the existing structures of the brain. There is a daily increase in the number of nerve cells. The hypothalamic-pituitary system begins to operate, which takes part in the management of the main autonomic functions of the body. The face of the fetus has already acquired quite human features: the eyes are still closed, but they are located in the place intended for them by nature, as well as the ears. nine0003

The baby periodically swallows a small amount of amniotic fluid. Part of the liquid is immediately pushed back, and the remaining water moves through the esophagus, thereby causing the activity of the digestive tract. The intestine responds first with chaotic and then organized contractions of the muscular walls. Very soon, muscle contractions will cause a peristaltic wave, which will help food move through the digestive tract. The liver has already begun to produce bile, which is necessary for the process of digestion of food. Gradually, the kidneys begin to work, which fill the bladder with the processed amniotic fluid. Urine is excreted into the amniotic fluid. nine0003

The uterus of a woman at the 12th week of pregnancy reached 12 cm in length and 9 cm in width. In the supine position, the expectant mother can feel her edge, which has grown to the pubic joint. Compared with the volume of the uterus of a non-pregnant woman, which is 10 ml., By the time of childbirth, the uterus increases by 500-1000 times and its volume can be from 5 to 10 liters.

With the completion of the first trimester of pregnancy, the hormonal function of the corpus luteum fades. The task of producing progesterone in full was taken over by the placenta. Women who suffered in early pregnancy from manifestations of toxicosis caused by the activity of the corpus luteum can breathe a sigh of relief: nausea, heartburn and vomiting have disappeared in most expectant mothers. Subsequently, many women remember this stage of pregnancy as the happiest time - good health and good mood give strength, and the stomach is still so small that it does not interfere with everyday life. nine0003

Before the twelfth week of pregnancy, every woman should undergo an ultrasound examination. Ultrasound will reveal fetal malformations and pregnancy risks. Also, accurate to the day, the gestational age will be determined. The doctor's conclusion indicates two terms: one for conception, the other - obstetric, which is considered from the beginning of the last menstruation. Most women are looking forward to the first ultrasound, because the genitals of the fetus have already acquired a fairly large size and the study allows you to determine the sex of the unborn baby. nine0003

12th week of pregnancy what happens to the fetus

The 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. nine0003

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 inner part of the ear is forming, but the auricle itself is not yet, 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. nine0032
• Muscles begin to master movements.
• The neck and larynx are forming - 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? nine0023

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. nine0003

Help! When choosing comfortable clothing, it is important to consider that it must be functional, made from natural hypoallergenic fabrics.

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