When Does the First Trimester End?
Pregnancy lasts approximately 40 weeks from start to finish, give or take a few weeks! But those first weeks, you may not even know you’re pregnant! The first trimester can seem like the shortest, because most women don’t confirm their pregnancy until it’s just about halfway over. So when does the first trimester end?
Because you’re probably completely unaware of what’s happening for the first six weeks or so, it can seem like the shortest trimester! When does the first trimester end, officially?
Pregnancies are divided into three trimesters. The first trimester starts at week one, and lasts through week 12. But again, you may not even realize you’re pregnant until week six, or possibly later! But just because you don’t know you’re pregnant doesn’t mean some pretty amazing stuff isn’t happening in your body.
Technically speaking, you’re not really pregnant at week one. Your pregnancy clock starts from the first day of your last menstrual period.
Ovulation happens in the second week, and by the third week, you could very well have a positive pregnancy test. By week four, you may be experiencing some common pregnancy symptoms, like bloating, nausea, breast tenderness, or fatigue. Week five and six is all about the development of your little fetus. Even though it’s only about the size of a grain of sand, it starts to develop arm and leg buds, blood is pumping through its circulatory system, and most organs have started to develop.
Weeks six – eight is when most women discover they’re actually pregnant! You may experience more first trimester symptoms, and will likely have your first prenatal check-up. Between weeks eight – nine, you may even be able to see the heartbeat for the first time. The fetus is now about an inch long, and while that is tiny, your belly may start to expand just a bit in the final weeks of your first trimester.
Before you know it, you’ve hit week 12, and that’s it! That is the official end of your first trimester.
So when does the first trimester end? Officially at 12 weeks gestation. But remember, you’ve probably only known about your pregnancy for half of that! After this, things start to change very quickly, and the second trimester holds lots of surprises!
(Image: iStock / fizkes)