Second trimester
18 weeks pregnant
Baby is about the size of a bell pepper.
Week 18 of 40 · in your second trimester · Updated
Your baby this week
Baby can definitely hear you now. Yawns, stretches, and rolls happen all day.
- Baby's hearing is well-developed. They respond to loud noises like a slamming door.
- Baby practices yawning, hiccupping, sucking, and swallowing.
- Myelin — the protective coating around nerves — starts forming. This will continue for the first year after birth.
Your body this week
Anatomy ultrasound is usually scheduled for weeks 18–22.
- The anatomy scan (mid-pregnancy ultrasound) is typically done around now. It checks baby's organs, growth, and placement of the placenta.
- Many women experience leg cramps, especially at night. Stretch your calves before bed.
- Your bump is making waistlines tighter — most women are clearly showing now.
Common symptoms
- Leg cramps
- Backache
- Swollen feet/hands
- Visible bump
- Talking to baby
Things to do this week
- Anatomy scan (18–22 weeks)
- Stretch calves before bed
- Eat bananas for potassium (helps cramps)
Tip
If you want to know the gender, this is when you can usually find out!
For partners this week
Anatomy scan season
- Book the time off to come to the anatomy scan.
- Talk about whether you both want to find out the sex, and how you'd share it.
Typical visits around this week
Based on a typical schedule in Ontario. Your doctor or midwife sets the actual timing.
Routine check-ups (about every 4 weeks)
Weeks 12–28
Check-ups are often about every 4 weeks until around 28 weeks. Your provider usually checks your blood pressure, weight and urine, listens to the baby's heartbeat and measures your growing belly. Some people need more visits.
Questions to ask →Questions to ask ↑
- Is my blood pressure and weight gain on track?
- Is this symptom I've been having normal?
- What should I be doing about exercise, work or travel right now?
- What's coming up before my next visit?
Anatomy (detailed) ultrasound
Weeks 18–22
A detailed ultrasound, usually at 18–22 weeks, that looks at the baby's brain, face, heart, spine, organs, arms and legs, and checks growth and where the placenta is.
Questions to ask →Questions to ask ↑
- Can my partner come, and can we have pictures?
- Where is the placenta, and does that matter for us?
- When will my provider go over the results with me?
- If we want to know the sex, can it be shared at this scan?
A flu shot and a COVID-19 vaccine are recommended at any stage of pregnancy. The flu shot is given during flu season, so the timing depends on when you're pregnant.
When to call your doctor or midwife
Bleeding, fluid leaking, a bad headache or vision changes, or baby moving less than usual all need a call. See the warning signs and who to call →
Follow your pregnancy week by week in MyBabyBase.
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Further reading from health authorities
- Pregnancy — Government of Canada (Public Health Agency of Canada)
- Your pregnancy — Pregnancy Info, from the Society of Obstetricians and Gynaecologists of Canada (SOGC)
- Week-by-week guide to pregnancy — NHS (UK)
- Pregnancy — American College of Obstetricians and Gynecologists (ACOG)