- 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!
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.
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:
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 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.
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.
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.
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're 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 baby up for a lifetime of better health!
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 sunblock (most experts recommend mineral-based for pregnancy) 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.
The shock of finding out you're having twins never really goes away, especially if you're a first-time parent. Even though the pregnancy was high-risk and difficult, I felt so lucky that I got to see my twins via ultrasound at every single prenatal appointment, more frequently than singleton pregnancies!
Please note: The Bump and the materials and information it contains are not intended to, and do not constitute, medical or other health advice or diagnosis and should not be used as such. You should always consult with a qualified physician or health professional about your specific circumstances.
American College of Obstetricians and Gynecologists, Exercise During Pregnancy, March 2022
American College of Obstetricians and Gynecologists, How Much Weight Should I Gain During Pregnancy?, August 2021
American College of Obstetricians and Gynecologists, Weight Gain During Pregnancy, January 2013
American Pregnancy Association, 12 Weeks Pregnant
American Pregnancy Association, Dizziness During Pregnancy
American Pregnancy Association, First-Trimester Screening
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March of Dimes, Common Discomforts of Pregnancy, March 2022
March of Dimes, Morning Sickness, September 2020
March of Dimes, Pregnancy Week-by-Week
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Mayo Clinic, Fetal Development: the 1st Semester, June 2022
National Partnership for Women & Families, Your Body Throughout Pregnancy
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