Your baby this week
7 weeks pregnant

In the know

The baby is growing a heart within its chest cavity. The heart only has two chambers so far, but will have four in a few months. Your baby is about 6mm (1/4 inch) long -- about as big as a tip of a match. See more about your little one's fetal development right here!

Plus sized & pregnant?

Plus-sized woman working out

"I'm a large woman (about 250 pounds) and want to be sure to have a healthy pregnancy. Do you have any prenatal exercise tips for me?"

Expert Lisa Stone, an ACE-certified Pre-and Post-Natal Fitness Instructor, has this to say: "Congratulations on taking an active role (no pun intended) on staying healthy during your pregnancy! You don't mention whether or not you were exercising prior to becoming pregnant, so I'll go on the assumption that you are new to fitness.

"If that's the case, then you'll want to start slowly, perhaps with a 10 to 15 minute moderately-paced walk on flat terrain. As you start to feel stronger, then you can add time to your walk in five-minute increments, gradually increasing to 45 minutes three to five times per week. Once you can walk that duration comfortably, try adding some low hills into your walking route to add intensity. Be sure to take along a bottle of water and take a big swig every 10 to 15 minutes so you stay well-hydrated."

To read the rest of her advice, click here.

Pin cushion time

<flower>If you're pregnant, it's not a great time to have a needle phobia! Blood work may be requested for a variety of tests to check on things that will impact your health and that of your baby.

Find out about some of the jabs and blood draws you might expect.

Smoke-free for baby

If you are a smoker, this may be the best time in your life to stop. Smoking can cause low birth weight in babies, and children born to mothers who smoked during pregnancy have been known to have lower IQ scores. It is also linked to miscarriage and fetal death after delivery, as well as complications such as placental abruption and placenta previa in the mother.

Put bluntly: each time you smoke, your baby does, too -- he will have nicotine passed into his bloodstream and placenta. This affects your baby's ability to get all of the important oxygen and nutrients that his body needs to grow.

Common sense dictates that smoking during pregnancy is not healthy for you or your that little person growing inside you. It's just that quitting can seem like a huge mountain to climb, especially when you're already experiencing so much change -- like adjusting to your ever-expanding waistline and getting used to the idea of becoming a new mama. 

Click here for great tips on how to kick the habit.

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