At 13 weeks pregnant, you're in the final week of your first trimester. (Can you believe you're already a third of the way through your pregnancy?!)

If you're like many parents-to-be, you may begin to tell people you're pregnant around week 13, but it's up to you when to give friends and family the news that baby is on the way.

Your Baby at Week 13

At a Glance

Eyes wide shut
Eyes wide shut
While baby’s eyes have arrived, they’re not open. His eyelids are fused shut to protect those tiny peepers as they continue to develop.
The voice
The voice
The promise of laughter, cries and very first words start now with the formation of vocal cords.
Balancing out
Balancing out
That big baby head is getting more in balance with the rest of the body. Right now, his head is about half the size of his total frame.

13 weeks pregnant is how many months?

If you're 13 weeks pregnant, you're in month 3 of your pregnancy. Only 6 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 13 weeks?

Besides being as large as a lemon now, that head of his is now about half the size of his crown-to-rump length. That's one reason why your little one looks more like an alien from outer space at this point. By the time you give birth, his body will catch up, measuring three-quarters of his total size.

But don't compare your fetus with the fetus next door. Starting in the next week or so, babies begin growing at different paces, some faster than others, some more slowly, though they all follow the same developmental path.

Baby's intestines and vocal cords are developing

What else is going on in there? At 13 weeks pregnant, tiny bones are beginning to form in his arms and legs. Because he can move them in a jerky fashion, he may be able to get his thumb into his mouth soon — a habit that may come in handy for self-soothing when he's a newborn.

Your baby's intestines are also in for some big changes. Until recently, they've been growing in a cavity inside the umbilical cord, but they've just moved into their permanent — and more conveniently located — address, in your baby's abdomen. And to serve your growing fetus' needs, the placenta is also growing, eventually weighing 1 to 2 pounds at birth.

Also developing this week: your baby's vocal cords (the first step toward saying, "I love you, Mommy!"). You obviously can't hear him crying or cooing just yet, but you can bet that little voice will get a good workout once he's born.

Your Body at Week 13

13 weeks pregnant woman

Feeling more like yourself?

Now that you're 13 weeks pregnant and just a week away from the second trimester, you should be feeling pretty good soon. After all, the second trimester doesn't get its reputation for being the easiest and most comfortable of the three for nothing.

But if you're not feeling better yet, don't worry. While most early pregnancy symptoms will probably be behind you soon, some women find that nausea and fatigue linger into the fourth and even fifth months.

And unfortunately for some women, those and other usual first trimester suspects — such as bloating, constipation, headaches and breast tenderness — can continue to some extent throughout pregnancy.

Vaginal discharge 

Of course, even though the second trimester is known as the trimester of smooth sailing, it doesn't mean you'll be symptom-free in the near future — far from it.

Something else you might have noticed recently is an increase in your vaginal discharge. Known as leukorrhea (try getting that right in a spelling bee), this perfectly normal discharge is thin and milky in color, or mild-smelling or sometimes even odorless. Plus, it'll probably increase as your pregnancy progresses.

Leukorrhea is caused by the stepped-up production of estrogen as well as the increased blood flow to the pelvic area. Its purpose is noble: to protect the birth canal from infection and maintain a healthy balance of bacteria in the vagina. Unfortunately, in achieving its lofty goal, leukorrhea can make a mess of your underwear.

If it makes you more comfortable, use a panty liner, never a tampon, to stay dry. But never douche while you're pregnant, which can upset the normal balance of microorganisms, lead to vaginal infections and even force air into the vagina during pregnancy, which can be dangerous.

Sex during pregnancy

With all the extra discharge down there plus your burgeoning belly, you may be wondering whether your feelings about jumping into bed are normal. Try to go with the flow: When it comes to pregnancy sex, anything goes.

You may not be in the mood at all or you may be up for sex a lot more than usual. All of it is normal and likely to continue fluctuating as your pregnancy progresses.

Having twins?

Your belly's already bursting out of the seams of your largest jeans and you're just finishing up the first trimester. Could you be having twins? Maybe — especially if you have a history of fraternal twins in your family or you're over 35 (or both).

But there are other more likely explanations for your seemingly larger-than-life belly. For instance, it could be that your due date's off and your bigger-than-expected tummy is the result of a bigger-than-expected baby.

Or it could be that you're just full of it — gas, that is. Bloating can make a pregnant abdomen distend well beyond its weeks. It's also possible that you're taking the eating-for-two mandate a little too literally — say, you took everything you ate before you became pregnant and doubled it, leading to your early midsection expansion.

To find out what's really going on in there, check with your practitioner at your next visit. Who knows — you just might have two buns in your oven after all. You can't tell from the outside, no matter what your grandmother says!

Pregnancy Symptoms Week 13

Decreasing fatigue
Decreasing fatigue
Food cravings and aversions
Food cravings and aversions
Heartburn and indigestion
Heartburn and indigestion
Constipation
Constipation
Visible veins
Visible veins
Faintness or dizziness
Faintness or dizziness

Tips for You This Week

Embrace your sex drive

Your second trimester is around the corner, and with it may come a boost in sex drive. Enjoy! What’s more, that spike in libido might have some health benefits for you and baby, since pregnancy sex can speed up postpartum recovery by tightening your pelvic floor muscles and improving your sleep and mood.

Not every woman will experience a super-sized sex drive (or any marked sex changes by trimester), however. So if your libido is lagging, don’t sweat it. 

If you have a history of preterm labor or miscarriage, you may need to abstain from sex during pregnancy (also known as pelvic rest). Talk to your doctor about what you're safely able to do.

Track your pregnancy symptoms

Now that you’re in your second trimester, you’re probably feeling a little bit better. Morning sickness may be (thankfully) behind you, and your energy levels have likely picked up. 

Still, a whole new set of pregnancy symptoms can pop up for the first time — including congestion, mild swelling and varicose veins. Track your symptoms to learn more about your ever-changing body and what’s going on in there.

Find pregnancy-safe food at restaurants

You may not always get the chance to choose the restaurant, but now that you’re pregnant, it’s time to seize the opportunity. 

If you're craving Italian, dine on grilled fish, chicken, veal or lean-beef entrees accompanied by gorgeous greens. If it’s Japanese food you want, enjoy teriyaki fish or chicken, miso soup, edamame and soba-noodle dishes.

And as long as your stomach's amenable to the spices in the cooking, Indian restaurants are another yummy, nutritious option — with plenty on the menu you can eat.

Don’t be shy about asking for substitutions if you need or want them. After all, you’re pregnant — so it’s especially important that what you eat is safe, healthy and appetizing.

Get used to the urine test

There’s one thing you can count on at every prenatal visit: the urine test. By taking a sample of your urine, your practitioner can test for some of the more common complications that can happen during pregnancy, including gestational diabetes, preeclampsia, and urinary tract infections.

For the most accurate results, start by washing your hands and wiping from front to back (your doctor will probably give you a wipe to use). Once you start peeing, catch the urine midstream with the collection cup. You’ll need about 1 to 2 ounces, so you may want to drink a glass of water before each visit.

Keep track of skin changes

It’s not unusual for moles to develop or change right about now, thanks to pregnancy hormones.

But it’s still a smart move to have them evaluated by your doctor. Always check in with your practitioner about any skin changes you notice, just to be safe.

Go for 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.

Eat iron-rich foods

When you're making a baby, you're in the blood-making business — big-time. Since iron helps generate blood supply, it's a nutrient you'll need plenty of to keep your body's and your baby's supply of red in the black.

Up your intake of this vital mineral by eating such iron-rich foods as beef, duck, soy products, spinach, dried fruits and potatoes with the skins on.

Your practitioner may also suggest a supplement after week 20 to keep your iron levels high enough as blood demand steps up. Just don’t take anything without your doctor’s approval.

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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  22. WhatToExpect.com, Best Maternity Underwear, According to Moms-to-Be Who Tried Them, December 2021.
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