Your pregnancy: 15 weeks

At nearly 10 centimetres (four inches) long, your baby is about the size of a tomato. Weighing just over 2.5 ounces (70 grams), he is practising his facial expressions, frowning, grimacing, squinting and wincing this week. At 15 weeks pregnant, your baby's hands are also making little fists, and he can even grasp them together. He is also breathing in small amounts of amniotic fluid, which is helping his lungs develop.

And he can hear now: Between your heartbeat and the blood coursing through the umbilical cord, it’s actually pretty noisy in your uterus. The baby can hear your (muffled) voice as well, and it’s important to him. By the time he is born, he’ll remember it: Studies have shown that newborns prefer their mothers’ voices to those of others.

Since you’re early in your second trimester, you’re probably feeling pretty good—though heartburn, residual nausea and pregnancy-related nosebleeds (thanks to increased blood flow to mucous membranes, coupled with sensitive skin) aren’t uncommon. If you’re lucky, you may even have that pregnancy glow, which is caused by a combination of increased blood flow (hello, rosy cheeks) and oil production in your skin. You’ll probably also find that your nails are growing faster and stronger and that your hair is thicker as well. You’re looking good, mama! If you’re not feeling the pregnancy glow, though, you’re not alone. Pregnancy doesn’t agree with everyone.

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Waking up every two hours to pee and tossing and turning from heartburn have an unexpected side effect: You’ll likely remember more of your dreams. Many women report more vivid dreams in pregnancy, too, possibly due to hormones. There’s also an old wives’ tale that if you dream that you’re having a girl, you’re actually having a boy—and vice versa.

Between week 15 and week 20 of your pregnancy, you’ll have the option of doing more prenatal tests to screen for neural tube defects. (You will also have a routine anatomy ultrasound scan between weeks 18 and 20.) Depending on where you are in the country and what you’ve done already, you’ll have either a quad screen or integrated biochemistry. The results will tell you the likelihood of your baby having neural tube defects such as spina bifida (where part of the neural tube doesn’t develop or close properly) and anencephaly (where a defect in the neural tube causes an underdeveloped brain and skull)—but not whether your baby has the issue or not. If you haven’t already been tested to determine your baby’s risk of chromosomal differences like Down’s syndrome, this test can tell you that as well. 

Now is a good time to reassess your pregnancy symptoms and see how they line up with all those old wives’ tales about expecting a boy versus expecting a girl. (Still feeling sick? How’s your skin? Are you craving sweets or salty foods?)

Have you loved animals since you were a kid? Take a look at these baby names inspired by the wildlife you adore.

Find a paediatrician

Here’s your first to-do that’s just for the baby: Find him a doctor. Your baby needs a doctor before he is even born—the hospital may not even release you unless you’ve lined up a healthcare provider. You might be surprised to learn that only one-third of kids see a pediatrician as their primary-care provider; the rest are cared for by family doctors and nurse practitioners. If you have a primary-care provider you love, consider asking him to take your baby on as a patient. If not, ask around for recommendations and consider location and after-hours availability as well.

If you’re starting to feel like pregnancy is taking its toll on you, you might want to give prenatal yoga a try. The stretching and strength exercises can help combat the lower back pain, headaches, anxiety and sleeplessness that are common during pregnancy, and the breathing exercises can help you handle the shortness of breath that comes later in pregnancy and possibly even the pain of contractions. Plus, the moves in prenatal yoga will help strengthen your pelvic floor, which makes it less likely that you’ll suffer from stress incontinence (that is, peeing your pants a little when you laugh, cough, sneeze, jump or run!) after birth. Regular yoga offers many of the same benefits, but some poses (such as deep or frequent twisting) aren’t recommended during pregnancy, so look for a teacher who has experience with pregnant women. 

Looking for a safe pregnancy workout? Give these 13 moves a try.

Bicep Curl

Get ready to carry your baby around (a lot!) by keeping your upper body strong.

How to: Standing tall with knees slightly bent, hold two hand weights at your sides with palms facing forward. Inhale with your core breath and, as you exhale, bend at the elbows and bring your hands towards your chest. Be sure to keep your wrists in neutral position at all times. Inhale and slowly lower to the starting position.

Beginner: Sit on a stability ball and use light weights.

Advanced: Do bicep curls standing on one leg.

This exercise works to stabilize the muscles that help support your pelvic girdle and control the way you walk.

How to: Standing tall, place a stability ball against a wall at thigh level. Place one hand on the wall for balance only. Stand as close to the wall as you can, holding the ball in place with your inside leg; bend that leg, keeping your knee back and legs parallel. Inhale using your core breath and, as you exhale, press the ball into the wall with your inside leg. Try not to lean into the wall. Repeat with the other leg.

Here’s a great upper-body exercise that tones and strengthens the posterior part of your arms.

How to: Standing tall, step back with your right leg and place your left hand on your left knee or a chair. Holding a hand weight in your right hand, bend your right arm and keep it close to your side while bringing your elbow back towards the ceiling. Leading with your core breath (see below), exhale, extend the arm back and squeeze your tricep. Inhale and bend. Keep your elbow up and back. Repeat with the other side.

How to: Sitting tall, place both hands around your side ribs. Imagine that your ribs are like a fan, your torso is an empty canister and there is a blueberry sitting between the front of your pelvis and your tailbone. As you inhale, open “the fan” out to the sides and fill up your ribs and “canister” with air, adjusting your posture (forward and back) until you find the most expansion. As you exhale, close the fan and “pick up the blueberry” with your pelvic floor, keeping your glutes relaxed. Repeat.

 TIP: This can be a tricky exercise to master. Start step-by-step, maybe even sticking with the expansive breath before you add the next step.

During pregnancy, there should be a focus on exercises like this, which strengthen posterior structures to help compensate for your growth out front.

How to: With resistance tubing at about waist height, stand tall with your knees slightly bent. Holding both handles with palms facing in, step back and extend your arms out in front of you. Inhale with your core breath and, as you exhale, pull the handles to your sides, bringing your elbows behind you; squeeze your shoulder blades. Inhale and return to starting position.

TIP: Wrap tubing around a banister, or exercise with a friend and take turns holding it while you encourage each other!

Strengthening your core during pregnancy is a must: These are the muscles that will help you push your baby out! Along with your pelvic floor, your core muscles need to be trained so you can use them to recover more quickly postpartum.

How to: Sitting tall on a stability ball, place both hands on either side for balance. Leading with your core breath, exhale and lift one foot off the floor and follow with the opposite arm over your head. Hold and breathe for 2 to 3 seconds. Return to starting position and repeat on the other side.

This exercise helps strengthen the external oblique muscles that support your growing uterus.

How to: Lying on your side, place one elbow directly under your shoulder for support. Bend both knees, stacking one on top of the other. Keeping the natural curve of your spine, begin with your core breath. Gently squeeze your butt and slowly bring your hips forward until your underside comes off the floor. Hold for 20 to 30 seconds, breathing normally. Don’t hold your breath! Repeat on the other side.

TIP: Later in pregnancy, your centre of gravity shifts up and forward, so balance and stability are key.

The squat strengthens your quads, hamstrings and glutes. Add a pelvic floor contraction and it’s a bonus.

How to: Stand tall with a stability ball between your back and the wall. Extend your arms out in front of you for balance. Leading with your tailbone, sit your bum back as if to lower into a chair; bend your knees, ensuring that they stay behind your toes. Inhale with your core breath on the way down; exhale while engaging your glute muscles and your pelvic floor to return to the starting position. Repeat.

TIP: Check your form! Work out across from a mirror if you can, or ask a friend to troubleshoot.

The lunge strengthens your quads, hamstrings and glutes – muscles that help carry around the extra weight of pregnancy.

How to: Stand tall and extend one leg behind you, keeping the heel up (place one hand on a chair for balance if you’d like). Leading with the back leg, inhale and bend the knee until both legs are at approximately 90-degree angles. Be sure to extend the back leg far enough behind you so the front knee stays behind your toes at the deepest point of the lunge. Exhale and return to the starting position. Repeat on the other side.

Advanced: Hold a weight in each hand while performing lunges.

This exercise helps keep your shoulders back and encourages proper posture.

How to: Standing tall with shoulders down and back, place one foot at the centre of exercise tubing, holding both handles. With the palms of your hands resting on the fronts of your thighs, begin with your core breath; bend your elbows and exhale while you lift both hands up towards your nipple line. Be sure to lead with your elbows first and keep your forearms angled towards the floor. Inhale and return your arms to the starting position.

TIP: Resist the tendency to lift your hands to your shoulders, which puts a lot of strain on your shoulder joints.

With the stability ball, a small movement can make a big impact. You will feel this in your chest, shoulders, biceps and forearms.

How to: Standing tall with knees slightly bent and shoulders down, hold the stability ball in front of you with hands on either side. Arms should be bent with your elbows out, parallel to the floor. Inhale with your core breath and exhale as you squeeze the ball. Be sure to keep your shoulders relaxed and do not allow the ball to rest on your chest.

How to: Sitting tall on a stability ball, place both hands on the sides of the ball for balance. Inhale with your core breath; slowly lift one foot off the floor and try to raise your knee while keeping the ball still. Exhale and extend the leg. Inhale and bend the knee to return to the start. Repeat with the other leg.

Beginner: Place the ball against a wall and put your foot down after each repetition.

Advanced: Move the ball away from the wall and keep your knee up until you’ve completed all your repetitions.

Although squats and lunges are great for all-around leg strength, a hamstring curl is a more isolated exercise for the backs of the thighs. Using a stability ball adds some core toning, too.

How to: Standing tall with your back against a wall, place your hands against the wall at your sides for support. Place one foot on top of the stability ball and find your balance. Starting with your core breath (see p. 33), inhale. As you exhale, dig your heel into the ball while slowly rolling the ball away from you. Keeping control of the ball, inhale and roll the ball back toward you, to the starting position. Repeat with the other leg.

Read more: Exercise: Myths about working out during pregnancy Baby bootcamp: Preparing for the delivery Next up: 16 weeks pregnant