At 16 weeks, you're officially 4 months pregnant!

As your second trimester hums along, your baby's growing rapidly, and you might start seeing changes to your own body, too — so if you haven't already gone shopping for maternity clothes, now's the time.

Your Baby at Week 16

At a Glance

Sensitive to light
Sensitive to light
Your baby’s eyes are making small side-to-side movements this week and can perceive some light, even though they’re still closed.
The sucking reflex
The sucking reflex
That thumb-sucking habit of many newborns may have already begun. At 16 weeks, babies may be able to make sucking motions.
Strong heart
Strong heart
Baby-to-be’s circulatory system is now up and (beginning) to run. In fact, that little heart can pump about 25 quarts of blood a day.

16 weeks pregnant is how many months?

If you're 16 weeks pregnant, you're in month 4 of your pregnancy. Only 5 months left to go! Still have questions? Here's some more information on how weeks, months and trimesters are broken down in pregnancy.

How big is my baby at 16 weeks?

Your baby now weighs in at a whopping 3 to 4 ounces and is 4 to 5 inches in length.

The backbone and tiny muscles in your baby's back are gaining strength, so she can straighten out that head and neck even more.

Baby's eyes are working

Thanks to those developing facial muscles, your baby is capable of making a few expressive frowns and squints, even at this early stage.

Baby's beautiful eyes are finally working too, making small side-to-side movements and perceiving light, although the eyelids are still sealed. Peekaboo!

Baby's skin is transparent

Your fetus is becoming a looker too — with a face that's starting to look more human — but a skinny looker, since there's no baby fat yet.

And here's the skinny on baby skin: It's practically translucent now, so if you took a peek inside your uterus, you'd be able to see your baby's blood vessels under that thin skin.

Baby will soon hear your voice

Listen up: Tiny bones in your fetus' ears are in place, making it likely that baby will soon be able to hear your voice (or something like it) when you're speaking. Generally, babies fully develop the ability to hear in the womb by 18 weeks of pregnancy.

In fact, studies have found that babies who hear a song while they're in the womb recognize the same tune when it's sung to them after they’re born — so choose your lullabies with that in mind.

Your Body at Week 16

baby size at 16 weeks pregnant

Rapid growth

At 16 weeks pregnant, your uterus is growing at about the same pace as your baby's — aka pretty darn fast! — and it's getting to the point where you may not be able to hide your pregnancy anymore, even if you wanted to.

You're still also likely enjoying the relative bliss of trimester two, especially compared with trimester one, and will soon be able to see more of your baby at your ultrasound in a few weeks.

Your 16 weeks pregnant belly

At 16 weeks pregnant, you may now be at the stage where your bump clearly has a baby in there. Your weight gain and that of your baby have likely picked up considerably, and you’ll both continue to grow. But all baby bumps at 16 weeks are different — and normal. Believe it or not, some women still don’t really show at 16 weeks pregnant, while others have pronounced bumps.

The wide variety of baby bumps can be attributed to everything from a woman’s size and shape to whether this is the first pregnancy or the second, third or fourth.

Whatever you do, don’t compare your 16 weeks pregnant belly to anyone else’s and don’t worry too much. It’s all good! If you’re still concerned, though, or have questions about how big or small you are, just talk to your doctor for some reassurance.

Your pregnancy weight gain

It may be hard to watch yourself gain weight during pregnancy, even when you know there's a wonderful reason for it, but try to embrace your body's new shape and think of every pound you put on as a sign of good health for you and your baby.

As long as you eat right during pregnancy, minimize junk and maximize nutrient-dense foods, and get regular exercise, you'll be fine in the long run. Remember, every woman gains and loses weight during pregnancy at a different pace.

One way to show your changing shape some love this week and feel better about yourself in the process: Buy a garment or accessory that makes you feel pretty at your new size — and don't forget to buy underwear that fits!

Nasal congestion

Your uterus is not the only thing that's starting to swell. So can the mucous membranes of your nose from all the pregnancy hormones circulating in your body, which are also increasing blood flow. The result? Your nose probably already knows: pregnancy congestion and possibly even nosebleeds.

Unfortunately, the stuffiness may only get worse as your pregnancy progresses, but your practitioner will probably not prescribe any medications or antihistamine nasal sprays to help clear things up — but do ask if your doctor recommends something else instead.

You can safely try saline sprays or nasal strips, especially if the congestion takes a turn for the truly uncomfortable. A humidifier in your room and a little petroleum jelly dabbed under your nose may also help overcome the dryness associated with any congestion.

Pregnancy Symptoms Week 16

Continued breast growth
Continued breast growth
Increased vaginal discharge
Increased vaginal discharge
Varicose veins
Varicose veins
Bleeding gums
Bleeding gums

Tips for You This Week

Choose soups

No matter the season, soups make a great midday meal. They can be as hearty as you want, pair well with others — we’re looking at you, sandwiches — and are often full of protein and fiber.

Eat em’ cold or eat em’ hot, and make a double batch of soup so you can freeze some for another time.

Switch to cotton underwear

An increase in vaginal discharge — known in medical-speak as leukorrhea — is often one of the first signs of pregnancy. It's also usually here to stay while you’re expecting, and the amount will likely increase as your pregnancy progresses.

Not to worry — this thin, white discharge is perfectly normal and healthy. Just keep the area clean and dry by bathing regularly and wearing breathable cotton underwear. If you're concerned about what you're seeing, call your doctor.

Use a humidifier

That annoying stuffiness in your nose — and sometimes even the nosebleeds that accompany it, especially if you're blowing often — usually start around week 16 of your pregnancy.

Unfortunately, they usually stick with you and sometimes get worse until the very end. Try using a neti pot with bottled, distilled water and a humidifier to moisten your dry nose.

Go for good calories when you exercise

When you're pregnant, you get to eat an extra 100 to 200 calories for every half hour of strenuous exercise you do.

But choose those calories wisely by eating nutrient-rich foods that won't undo the benefits of all your hard work.

Try to pass up that chocolate bar you were about to reach for. (That energy bar probably isn't much better, either.) Instead, go for a smoothie or a granola-yogurt parfait, some apple slices smeared with almond or peanut butter, or whole grain crackers and cheese.

Manage back pain

Backache got you down? Instead of nursing it on the sofa, try doing some gentle yoga or Pilates. Both help stretch and loosen the spine and release tension — which can be one of the main causes of back pain.

Another plus: Yoga and Pilates boost your overall energy and mood levels, so you're better able to cope with the pregnancy pains that remain.

You can also do simple moves that strengthen your abdominal muscles, which will, in turn, reduce the amount of strain on your lower back. (But remember, don't exercise on your back now that you're well into your second trimester).

Go for greens

Make a habit of having a salad or grilled veggies, or sauteéd leafy greens such as spinach, escarole or broccoli as a side.

Lentil, bean and vegetable soups are all great choices too, and same goes for tomato-based broths and chowders.

Prepare for the quad screen

The quad screen is a blood test that measures the levels of four substances produced by the fetus and the placenta, which are then passed into the mother's bloodstream.

The results tell you what the probability is that you're carrying a child with a chromosomal abnormality or neural tube defect.

Quad screen results can be combined with those from the nuchal translucency (NT) screening or the noninvasive prenatal testing (NIPT) to give you a more accurate assessment.

From the What to Expect editorial team and Heidi Murkoff, author of What to Expect When You're Expecting. What to Expect follows strict reporting guidelines and uses only credible sources, such as peer-reviewed studies, academic research institutions and highly respected health organizations. Learn how we keep our content accurate and up-to-date by reading our medical review and editorial policy.

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