Week 17 of Pregnancy
Learn about your baby's development and what to expect at 17 weeks pregnant.
Baby's Size This Week
Baby Development at Week 17
- ● Your baby is now 13.0 cm long and weighs about 140g — roughly the size of a pear.
- ● Vernix caseosa (a protective waxy coating) is beginning to appear on the skin to protect it from prolonged exposure to amniotic fluid.
- ● Lanugo (fine downy hair) covers the entire body and helps hold the vernix in place against the skin.
- ● Your baby can hear sounds from outside the womb, including your voice, music, and environmental sounds.
- ● The sweat glands are developing, and fat deposits are beginning to accumulate under the skin for warmth and energy.
- ● Cartilage throughout the body is continuing to ossify (harden into bone), and the skeleton is becoming more rigid and defined.
Your Body at Week 17
- ● Around week 17, many women feel their baby's first clear flutters of movement (quickening) — often described as bubbles or gentle tapping.
- ● Round ligament pain — brief, sharp pains on the sides of your abdomen — is common as the uterus expands and ligaments stretch.
- ● Your appetite may increase significantly; focus on nutrient-dense foods and stay well hydrated throughout the day.
- ● Backache and pelvic discomfort may increase as relaxin loosens your joints and your center of gravity shifts forward.
- ● Nasal congestion may worsen due to increased blood flow to mucous membranes, and nosebleeds can occur.
- ● Your skin may develop stretch marks as the belly expands — moisturizing regularly can improve skin elasticity.
Week 17 Checklist
- ☐ Confirm your anatomy scan appointment is scheduled between weeks 18-20.
- ☐ Begin a daily movement awareness practice — at 17 weeks, movement is irregular but should gradually increase.
- ☐ Stay active with low-impact exercise: walking, swimming, prenatal yoga, or stationary cycling.
- ☐ Focus on adequate iron, calcium, and omega-3 (DHA) intake to support fetal brain and bone development.
- ☐ Consider a pregnancy support belt if back or pelvic pain is affecting your daily activities.
- ☐ Begin researching pediatricians and schedule prenatal consultation appointments with your top choices.
Frequently Asked Questions
What should I expect at 17 weeks pregnant?
At 17 weeks, you are in the heart of the second trimester. Your baby weighs about 140g and is developing hearing, fat stores, and a protective vernix coating. Most women feel distinctly more energetic than the first trimester, and many begin feeling fetal movement this week. Your anatomy scan is coming up in 1-3 weeks — an exciting milestone.
What does quickening feel like and how do I know it's the baby?
Quickening — the first sensation of fetal movement — is often described as fluttering butterflies, popping bubbles, a gentle tapping, or a fish flipping. It is usually felt low in the abdomen. It can be hard to distinguish from gas early on, but movement tends to come and go rather than being continuous. As weeks progress, sensations become stronger and more clearly rhythmic. If you are uncertain, your provider can confirm at your next visit.
Is it safe to lie on my back at 17 weeks?
Occasional back sleeping at 17 weeks is generally not harmful, but as the uterus grows, it can compress the inferior vena cava (the large vein returning blood from your lower body to your heart) when you lie flat. This can reduce blood flow and cause dizziness. Most providers recommend transitioning to left-side sleeping by 20 weeks. Use a pregnancy pillow to stay comfortable on your side.
Should I be talking to my baby at 17 weeks?
Yes. Your baby can hear sounds from outside the womb beginning around weeks 16-18. Your voice is transmitted through your body and amniotic fluid. Research shows that newborns recognize their mother's voice, suggesting that prenatal exposure to your voice creates familiarity. Talking, reading aloud, singing, or playing calming music are all beneficial ways to connect with your baby before birth.
What can I eat to prevent stretch marks?
No topical treatment has been proven to fully prevent stretch marks, as they are largely determined by genetics and skin elasticity. However, staying well hydrated, applying moisturizers containing vitamin E, shea butter, or cocoa butter, and gaining weight gradually within the recommended range can minimize their severity. Stretch marks often fade from red or purple to silver over time after delivery.
Track Your Exact Pregnancy Week
Use our free Pregnancy Week Tracker to find out exactly how far along you are based on your last menstrual period or due date.
Track My Pregnancy →Sources
- ACOG
- WHO Fetal Growth Charts
- Mayo Clinic
Medical disclaimer: This content is for informational purposes only and is not intended as medical advice. Always consult a qualified healthcare provider for guidance specific to your pregnancy.