Pregnancy Week by Week: Your Complete 40-Week Guide

Follow your pregnancy journey from conception to birth with our comprehensive week-by-week guide. Track your baby's development, understand your symptoms, and prepare for each milestone.

ACOG-Aligned ContentUpdated August 2026How We Create Content

Understanding Your Pregnancy Journey

Pregnancy is typically measured as 40 weeks, starting from the first day of your last menstrual period (LMP). This is the standard dating method used by healthcare providers, even though conception usually occurs around week 2. Your pregnancy is divided into three trimesters, each with unique developmental milestones and experiences.

๐ŸŒฑ First Trimester (Weeks 1-13)

Rapid development occurs as all major organs form. You may experience morning sickness, fatigue, and breast tenderness. The first trimester includes important prenatal screenings and your first ultrasound.

Learn more about first trimester

๐ŸŒฟ Second Trimester (Weeks 14-27)

Often called the "honeymoon phase" as many early symptoms ease. You'll feel baby's first movements and have the anatomy scan. Energy levels typically improve during this time.

Learn more about second trimester

๐ŸŒณ Third Trimester (Weeks 28-40)

Baby grows rapidly and positions for birth. Prenatal visits become more frequent. This is the time to prepare for labor, set up the nursery, and finalize your birth plan.

Learn more about third trimester

Medical Notice: This week-by-week guide provides general information about typical pregnancy progression. Every pregnancy is unique. The information here should complement, not replace, advice from your healthcare provider. Always consult your OB-GYN or midwife with questions about your specific pregnancy. Read full disclaimer

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First Trimester

Weeks 1-13

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Second Trimester

Weeks 14-27

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Third Trimester

Weeks 28-40

๐Ÿ›๏ธ Pregnancy Essentials for Every Week

Comfort and preparation products other expecting parents find helpful at this stage. These are convenience picks, not medical advice โ€” always follow your provider's guidance.

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Prenatal Vitamins (with Folate & DHA)

โ˜…โ˜…โ˜…โ˜…ยฝ4.8

Daily folate, iron and DHA support that doctors recommend before and throughout pregnancy.

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Full-Body Pregnancy Pillow

โ˜…โ˜…โ˜…โ˜…ยฝ4.7

U-shaped support for side-sleeping that helps take pressure off hips and back.

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What to Expect When You're Expecting

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The classic week-by-week guide trusted by millions of expecting parents.

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๐Ÿงด

Belly Butter / Stretch-Mark Cream

โ˜…โ˜…โ˜…โ˜…ยฝ4.7

Rich cocoa-butter moisturizer to keep a growing belly comfortable and hydrated.

Check Price on Amazon โ†’

Amazon Associates Disclosure: As an Amazon Associate, we earn from qualifying purchases at no extra cost to you. These recommendations are editorially chosen comfort and preparation products and are not medical advice.

Helpful Pregnancy Resources

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Evidence-Based Pregnancy Information

Our week-by-week pregnancy content is developed based on guidelines from the American College of Obstetricians and Gynecologists (ACOG), Centers for Disease Control and Prevention (CDC), National Institutes of Health (NIH), and peer-reviewed medical literature.