It's probable you just learned about your pregnancy this week, after missing your period for too many days to be normal. If so, congratulations, mama! If you're interested to find out what's been taking place in your body, read back through weeks 3 and 4. And then head into Week 5 to find out three things to expect from your baby and your body this week.

1. Big News Week!

Many women learn about their pregnancies for the first time this week! But your little didn't wait for you to find out to start growing and developing. That embryo holding court in your belly is still teeny-tiny: the size of an orange seed, 1/16th to 1/8th of an inch! That measurement is from crown to rump, which is the way they are taken until gestational week 13. Speaking of gestational weeks, have you figured out your due date yet? Use our calculator now to find out your baby's estimated due date!

2. Eyes, Ears, and a Heart, Oh My!

This week, the fetal skeleton and the structures that will become the eyes and ears are beginning to take shape. Also, your tiny sweetie's heart and circulatory system are forming! The heart is currently made up of two tiny channels called heart tubes, the beats of which your doctor just might be able to pick up on an ultrasound. Eventually those two tubes will fuse together to become the heart.

3. Below the Belt

During these early weeks of pregnancy some women experience very light spotting and/or gentle cramping. It's not necessarily anything to be concerned about, but it's always worth a mention to your doctor. Bleeding that resembles a period with strong cramps could be a sign of miscarriage; call your doctor right away if you experience any bleeding.