Stages of Pregnancy Week by Week

What My Baby Looks Like in Week 1

Conception hasn't occurred yet in week one of your first trimester, but your uterus is getting prepared for fertilization.

My Baby Week 1

More about Week 1

Week 2
After your last menstrual period the uterus lining begins to thicken with blood vessels as it prepares for fertilization. During the first week of "pregnancy" actual conception has not yet occurred. Your uterus and ovaries are preparing for fertilization.
Illustrations Courtesy of the Sprout Pregnancy App

Illustrations Courtesy of the Sprout Pregnancy App

Track your baby's development on your iPhone and iPad and keep important pregnancy details at your fingertips.
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An Inside Look

Take a unique look at Baby's development inside the womb this week.

Your Growing Belly

A month-by-month photo gallery of pregnancy.

Your Growing Baby

Your baby is just a tiny egg waiting to unite with a sperm.

Your Pregnancy Week 1

Learn more about what's happening with your pregnancy this week including your baby's latest fetal development milestones, your changing body, and tips to help you along the way.

My Pre-Pregnancy Checklist

A healthy pregnancy begins long before that stick turns pink. Get baby-ready with these smart steps for your life, health, and finances.

Ask a Question

Got a question? We've got answers from experts and parents who've been there.

29 Ways to Chart Your Pregnancy Needs

Be prepared to share your detailed information with everyone: your medical history with your doctor, your 1 AM pickle cravings with your partner, and your contractions with your prenatal provider. Our A-Z pregnancy downloads make things easy!

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