Pregnancy by week

Your pregnancy: 13 weeks

Welcome to your second trimester. Believe it or not, your baby’s body has doubled in length since week 7 and he’s as big as a large plum or a peach.

By Today's Parent

Your pregnancy: 13 weeks

Photo: Mandy Milks, Erik Putz, Anthony Swaneveld. Felt:

What's going on in there: Fetal development at 13 weeks

At 13 weeks pregnant, your baby has grown again: He’s almost as big as a cookie now, clocking in at nearly eight centimetres (three inches) long and weighing nearly 25 grams (0.9 ounces). His arms are about the right length for his body, but his legs are a little stubby (no offence, little buddy). A lot is happening all at once: His vocal cords are further developing, his intestines are moving into their proper place, he is creating (and peeing out!) his own urine into the amniotic fluid, and he is even starting to grow his own unique fingerprints.

13 weeks pregnant symptoms

Worth the weight You’re growing, too! While many women gain upwards of five pounds in the first trimester, most start gaining as much as one pound a week from 13 weeks pregnant until birth. Gaining about 14 pounds over the course of the second trimester is the average. (To see how much you should gain for your body mass index (BMI), check out Health Canada’s calculator.) Keep weight gain at a healthy rate by shifting your thinking away from “eating for two” and towards adding an extra snack to your day. You only need about 300 extra calories a day when you’re pregnant, which is equivalent to one extra piece of fruit and a cup of yogurt.

Now that your first trimester is almost over, you might even feel like eating again. The nausea and low energy that are common at the beginning of your pregnancy often ease up around now. For many women, the second trimester is a nice time: You’re past fatigue and morning sickness, you can tell people what’s happening, and you’re not so big that you’re feeling uncomfortable or less mobile. Enjoy it!

Achoo! Hormones are to blame for the nasal congestion and runny noses that about 30 percent of pregnant women experience, known as rhinitis of pregnancy. This kind of stuffed-up nose doesn’t come with the other symptoms of allergies or the common cold. Estrogen causes the mucous membranes to swell and produce more mucus. The blood vessels lining your nasal passages are also inflamed. In some cases, this double whammy can lead to a sinus infection or sinusitis (symptoms may include fever, headaches, green or yellow mucus, facial pain or pressure, sore teeth or a sore upper jaw and a reduced sense of smell), which needs to be treated by a doctor (and possibly antibiotics).

Many cold medications and decongestants aren’t safe during pregnancy. (Call the Motherisk helpline at 1-877-439-2744 or visit if you aren’t sure.) Instead, you can treat congestion safely by rinsing your nasal passages with saline water (using a bulb, a neti pot or a saline rinse bottle from the pharmacy), a warm shower in a steamy bathroom, a warm facecloth on your face, over-the-counter saline nose drops (avoid the kind with decongestants) or a vapourizer (keep the water clean and check the filter, too) or by adding an extra pillow to keep you propped up at night. Other symptoms, such as coughing or aches and pains, might indicate the cold or a flu, and itchy eyes could mean allergies.

What's on your mind this week?

Think about getting on a daycare list Sadly, we’re not kidding. If you’re in a city where daycare is in high demand, it’s not too early (or too Tiger Mom mode) to put your unborn child on a few daycare lists. In fact, it’s often necessary. Though it will be illegal for licenced Ontario daycare centres to charge parents a fee to be on a wait list starting September 1, the practice persists in some provinces. When you’re making your list of potential daycare centres, check out co-ops and non-profits, which can be less expensive, and find out if your workplace has a deal with any child care providers, which might guarantee your future offspring’s admission. Infant spots (0 to 18 months) tend to be the priciest (the equivalent of your monthly rent or a mortgage payment—gulp!) and then decrease gradually during the toddler and preschool years. Learn more about the differences between daycare centres and home daycares here, and bookmark this list of questions to ask about daycares before going on any tours. 

Why am I so horny? Surging hormones can make you feel like a teenager again, and increased blood flow can make your orgasms during pregnancy even better. Don’t worry about getting down: Your baby is well protected at all stages of pregnancy by a thick amniotic sac, the uterus and the mucus plug (in your cervix). Women with low-risk pregnancies can have sex right up until their water breaks or they go into labour. In fact, many women with full-term pregnancies try sex as a way to jumpstart labour. (To be clear, a roll in the hay at this stage in your pregnancy won’t cause you to deliver prematurely.)

Just for kicks

Our deputy editor’s hilarious take, in comic strip form, on attempting super-pregnant sex.

Baby names

This baby name has become shockingly unpopular recently. Can you guess what name it is? 

Pregnancy to-do list: Week 13

Switch up how you sleep Although not all experts agree, some doctors recommend that you don’t sleep on your back during the second and third trimesters because it puts the weight of your uterus on a large vein called the inferior vena cava, which runs behind your organs, close to your spine. This can interfere with digestion and circulation, cause backaches and affect the baby because it reduces blood flow to the fetus. The optimal sleeping position for blood flow during pregnancy is on your left side (“Left is best” might help you remember this). Many women find that they feel better when they sleep on their sides, with a dense pillow propped between their knees or snuggled against a full-body pregnancy pillow or bolster (we've picked a few of our favourites below). If you wake up on your back, don’t panic: It’s your body’s way of telling you to roll over. Just switch positions and try to start the night on your side.

Pregnancy pillows

Leachco Snoogle Total Body Pillow

Chic Jersey, Heather Grey. $95,

Snoogle grey hook shaped pregnancy body pillow

Boppy Pregnancy Wedge Pillow

Petite Trellis. $21,

Grey and white patterned pregnancy pillow wedge

Baby Works Maternity & Beyond 3-in-1 Pillow

Microbead Body Pillow by Deluxe Comfort

Leachco Back ‘N Belly On My Own Body Pillow

Splash Taupe. $170,

Pink floral pattern back and belly pregnancy pillow

My Brest Friend 3-in-1 Body Pillow

White. $58,

White My Brest Friend pregnancy body pillow

Jolly Jumper Wedge-Eze


Chevron grey and white pregnancy pillow wedge

KidiComfort Body Pillow

DreamWeaver Full Body Pillow


White candy cane shaped body pillow

Take care of your teeth Hormonal changes can make your gums more sensitive during pregnancy, making it harder for the bacteria in your mouth to fight off plaque and causing pregnancy gingivitis. In fact, most moms-to-be have soft or bleeding gums. You can help prevent them by brushing twice a day, flossing daily and booking an appointment to see your dentist at least once while you’re pregnant.

Read more: Are baby showers still an important tradition? Pregnancy sleep: Slumber for two Next up: 14 weeks pregnant

Your pregnancy: 13 weeks

This article was originally published on Aug 25, 2017