Week 13 of Your Pregnancy

Verywell / Bailey Mariner

You're in the last week of your first trimester. At 13 weeks pregnant, your baby can swallow and make urine. Meanwhile, you may begin to notice some new symptoms, like unwelcome skin changes.

13 Weeks Pregnant Is How Many Months? 3 months and 1 week

Which Trimester? First trimester

How Many Weeks to Go? 27 weeks

Your Baby's Development at 13 Weeks

At 13 weeks, a baby is approximately 3 inches in length (7.5 centimeters).

At 13 weeks pregnant, your baby is about the length of baby booties
Verywell / Bailey Mariner 

Baby Hair

Hair follicles have already started developing, and soft, fine hair called lanugo is beginning to appear. By 20 weeks, lanugo will cover your baby's body. The hair holds a substance called vernix on baby’s skin to coat and protect it from the amniotic fluid.


Your baby can swallow and is swallowing up the surrounding amniotic fluid.

Urine Production

Baby's bladder can be seen with an ultrasound, and the kidneys are producing urine that becomes part of the amniotic fluid.


Ten tiny fingertips are developing ridges that will hold baby’s everlasting and unique fingerprints. The fingerprints will be fully formed in a few more weeks.

Growing Placenta

The placenta provides your baby with oxygen and nutrients. It also filters out waste. While it is now fully functioning, it continues to grow and change throughout pregnancy.

Explore a few of your baby's week 13 milestones in this interactive experience.

Stay Calm Mom: Episode 3

Watch all episodes of our Stay Calm Mom video series and follow along as our host Tiffany Small talks to a diverse group of women and top doctors to get real answers to the biggest pregnancy questions.


How Will Pregnancy Change My Body?

Your Common Symptoms This Week

As you near the end of the first trimester, nausea may begin to fade. However, you may still be dealing with constipation or heartburn. New symptoms may also arise as your pregnancy progresses.

Vaginal Discharge

White or clear vaginal discharge is normal, even when you aren't pregnant. But, during pregnancy, the amount of discharge or leukorrhea increases. You may notice more of a thin, whitish fluid than you did before. It's common and not a cause for concern.

Stretch Marks

Fifty to ninety percent of expectant parents develop stretch marks. These purple or red lines appear on the belly, breasts, or thighs. When they fade, they leave pale lines on the skin.

Stretch marks tend to show up when the skin grows and stretches very quickly. Genetics and hormones also play a part. Pregnancy is a time of rapid growth, weight gain, and hormone changes, so it's a common time to experience stretch marks.

Self-Care Tips

As the weeks go on, you may be able to eat a little bit more. You may also want to try to keep those "stripes" to a minimum and pay attention to any vaginal discharge you may be experiencing.


Since your nausea is very likely waning, now is a great time to start expanding your healthy eating choices.

What Experts Say

“This month is a great time to boost your intake of calcium, vitamin D, and magnesium, as each helps with baby’s rapidly developing bones and teeth.”

—Dana Angelo White, MS, RD

Some healthy choices include:

  • Calcium: Broccoli, fortified foods such as soy milk, fruit juices, tofu, and cereal
  • Magnesium: Spinach, nuts, seeds, beans, whole grains, and avocados
  • Vitamin D: Egg yolks, fatty fish, sardines, and fortified milk

Skin Care

You cannot prevent stretch marks. But, you can try to keep them to a minimum by:

What Experts Say

“There’s really no way to prevent stretch marks. Often, these marks will fade over time."

—Allison Hill, MD, OB/GYN

You can moisturize your skin, but creams and lotions cannot prevent stretch marks. Stretch marks develop in the second layer of skin called the dermis. The lotions and creams absorb into the top layer of the skin (the epidermis). You should also beware that some products may contain ingredients that aren't safe during pregnancy. So, use caution.

If you want to do something about your stretch marks after your pregnancy, you can consult with a dermatologist about treatments or procedures to fade or remove them.

Dealing With Discharge

An increase in thin, clear, or white vaginal discharge is normal during pregnancy. You can deal with it by wearing a pantyliner and keeping the area clean and dry. However, changes in discharge can sometimes be a sign of an infection. So, notify your doctor if the discharge:

  • Is abundant
  • Changes in color to yellow or green
  • Has an odor
  • Is accompanied by pain, itching, or redness in the area

Your Week 13 Checklist

Advice for Partners

Feeling sick alongside your partner and not sure why? Don't worry—you're not the only one. Some partners experience sympathetic pregnancy symptoms, also known as couvade syndrome, at the end of the first trimester. That’s right—you may be gaining weight or feeling queasy right along with your pregnant partner.

According to a 2013 study published in the journal Medical Science Monitor, the frequency of couvade symptoms is associated with empathy. So, if you’re not feeling the best, you're not copy-catting for attention. You’re simply more emotionally sensitive and understanding of your partner's feelings.

At Your Doctor’s Office

If you did not see your healthcare provider for your second prenatal visit last week, you’ll likely be on your way this week. The doctor will check your:

The doctor or midwife may also use a Doppler—a handheld instrument that’s placed on your abdomen, over your uterus—to check your baby’s heart rate. With this, you’ll get to hear the precious thump-thump of your baby’s heartbeat.

Upcoming Doctor’s Visits

  • Your next routine prenatal visit will be around week 16.
  • An amniocentesis, if you, your partner, and doctor decide on it, is typically performed between week 15 and week 20.

Recommended Products

If you want to try to keep stretch marks away or moisturize any lines that may be appearing, be sure to use a product with safe ingredients.

Stretch Mark Creams

While evidence that creams and lotions are effective to prevent stretch marks is lacking, they may be worth a try. At the very least, they can keep your skin moisturized and hydrated. It may even make your skin feel softer and smoother. Just remember to choose a natural product and talk to your doctor or a dermatologist about ingredients you aren't sure about.

Special Considerations

This week, your doctor may perform a procedure to protect pregnancy for parents who have lost a child in the second trimester, have a history of painless cervical dilation in the second trimester, or have had a previous cerclage. It's also a good time to consider whether or not you're happy with your healthcare provider.

Cervical Cerclage

If you have a history of cervical insufficiency, sometimes called an incompetent or weak cervix, your healthcare provider may talk to you about getting a cervical cerclage. It is typically placed between week 13 and week 14 of pregnancy.

During this procedure, you receive either general, spinal, or epidural anesthesia, while a surgeon stitches around the cervix to help prevent it from shortening and opening too early, causing preterm birth. The stitches can be removed in your healthcare provider’s office at 37 weeks.

Changing Doctors

You’ve already had your first prenatal visit with your healthcare provider. Did you feel supported and listened to? Is your doctor or midwife responsive and respectful when you have questions or concerns? Know that if you don’t think your healthcare provider is the right fit, you have every right—even an obligation—to switch.

If you do decide to change providers, know that the process isn’t complicated. All you need to do is sign a release to transfer your medical records. If you don’t want to confront your healthcare provider face-to-face, simply have your new provider process the release.

A Word From Verywell

It is the end of the first trimester. In 13 short weeks, your baby has grown from a tiny combination of an egg and a sperm into a fully formed little human. Of course, there's still a bit of growing and maturing to do before that little life can survive on their own outside your womb.

Next week brings a big pregnancy milestone. It may mean some relief of your early pregnancy symptoms and a boost of energy.

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Verywell Family uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Additional Reading
  • Lang J, White DA. The Whole 9 Months: A Week-By-Week Pregnancy Nutrition Guide with Recipes for a Healthy Start. Arcas Publishing.

By Holly Pevzner
Holly Pevzner is an award-winning writer who specializes in health, nutrition, parenting, and family travel.