Pregnancy Stages - Week by Week Prenatal Development Guide

Guides to Stages of Pregnancy Development Week by Week

From early, mid-, and late pregnancy, through those final big weeks, take a week-by-week look at what you’re creating, how you might feel, and ways you can prepare!

First trimester: your journey begins

From your prenatal preparation through week 12 of your pregnancy, get the inside scoop on this early part of your fascinating new journey. 

Second trimester: the magical middle months

You and your baby are almost (or more than) halfway home! There’s much to love about this stage and lots to know about taking care of you both.

Entering third trimester: the home stretch!

Find out what weeks 28-36 have in store for you and your not-so-little one! Changes abound and we’re here with helpful support.

Week 37: from pregnancy to parenthood

Your pregnancy journey is ending as preparations for parenthood begin. Here’s a little information to help you get ready for the big day!

Week 38: preparing your body and mind

Your big date's in sight and you can’t wait to meet your baby! See our planning checklist and other insights to help guide your preparations.  

Week 39: the finish line is in sight 

Your little one will arrive any day now, and there are still some important things to think about and do before your labor begins. 

Week 40: is today the day?

Your due date and baby’s birth date are likely not the same. Find out why, as well as other things to consider in these exciting last days of pregnancy!


Join MySimilac® Rewards. It’s fast and FREE!

Postnatal Popup
  • Baby Formula coupons and samples
  • Nutrition guidance for you and baby
  • Free† Shutterfly® photo book
  • Savings on Schedule & Save purchases

† Submit registration to read details.

Join MySimilac® Rewards. It’s fast and FREE!

Prenatal Popup
  • Free Shutterfly® photo book
  • Nutrition guidance for your pregnancy
  • Information about your baby’s milestones

Submit registration to read details.

Instead of paper coupons, receive Similac® digital offers

Digital Offers Popup

Now you can switch to digital savings by phone on your favorite formulas—here’s how:

  1. Choose a preferred retailer, like Amazon or Target
  2. Get notified about offers via email