Pregnancy Stages?

Help me understand the stages of pregnancy. What will happen when?
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Updated March 2, 2017
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We know, we know. It’s kind of confusing! And to make matters worse, some doctors count the stages, or trimesters, of  pregnancy slightly differently. Here’s how we do it here at The Bump (based on what our OB friends have told us, of course!):




First trimester

OBs count your pregnancy starting with the first day of your last period (LMP) — before you even conceived! So you might not even know you’re pregnant until week 4, week 5 or even later. Your first trimester goes from your LMP until the end of week 13.

The first trimester is known for its symptoms — mainly nausea and total exhaustion — and for getting adjusted to the idea of being pregnant. There are a lot of changes!

Get the full scoop on the first trimester.

Second trimester

Known as the “honeymoon period” of pregnancy, the second trimester is the time most moms-to-be feel best, getting their energy and appetite back. It’s also the time you’ll find out more about your baby — including the gender, if you want to know! It lasts from week 14 to the end of week 27.

Get the full scoop on the second trimester.

Third trimester

The third trimester is all about prepping for baby — your body, your home and your life! Sorry, but this phase can be a little uncomfortable. Your body will get much bigger and heavier and you might have some trouble sleeping. But it will all be worth it when you’re holding your newborn in your arms. The final trimester lasts from week 28 until you deliver your baby. (Your estimated due date will be the first day of week 40, but baby could be early or late!)

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Get the full scoop on the third trimester.

Still confused what trimester you’re in? Use our Due Date Calculator to get specific dates, based on when you had your LMP. And if you don’t know when you had your period last, don’t worry! Your OB will be able to estimate how far along you are with an ultrasound.


Pregnancy weeks


As you travel along this crazy (but awesome) pregnancy journey, you’ll probably not just count the trimesters, but also the weeks. And yes, there are new things to learn about baby’s development and what’s happening with your body each week. So follow along using our  Pregnancy Week-by-Week guide.

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