How your baby's growing:It's hard to say for sure how big your baby will be, but the average newborn weighs about 7 1/2 pounds (a small pumpkin) and is about 20 inches long. His skull bones are not yet fused, which allows them to overlap a bit if it's a snug fit through the birth canal during labor. This so-called "molding" is the reason your baby's noggin may look a little conehead-ish after birth. Rest assured — it's normal and temporary.
How your life's changing:After months of anticipation, your due date rolls around, and... you're still pregnant. It's a frustrating, but common, situation in which to find yourself. You may not be as late as you think, especially if you're relying solely on a due date calculated from the day of your last period because sometimes women ovulate later than expected. Even with reliable dating, some women have prolonged pregnancies for no apparent reason.
You still have a couple of weeks before you'll be considered "post-term." But to be sure your baby is still thriving, your practitioner will schedule you for testing to keep an eye on her if your pregnancy continues.
biophysical profile (BPP), which consists of an ultrasound to look at your baby's overall movements, breathing movements (movement of her chest muscles and diaphragm), and muscle tone (whether she opens and closes her hand or extends and then flexes her limbs), as well as the amount of amniotic fluid that surrounds her (important because it's a reflection of how well the placenta is supporting your baby).
Fetal heart rate monitoring (called a nonstress test or NST) will generally be done as well — by itself or as part of the BPP. Or, you may have what's known as a modified BPP, which consists of an NST and an ultrasound to assess the amount of amniotic fluid.
If the fetal testing isn't reassuring — the amniotic fluid level is too low, for example — you'll be induced. If there's a serious, urgent problem, you may have an immediate c-section.
Your practitioner will also check your cervix to see if it's "ripening." Its position, how soft it is, how effaced (thinned out) it is, and how dilated (open) it is can all affect when and how your labor is induced. If you don't go into labor on your own, you'll be induced, usually sometime between 41 and 42 weeks.
Shared from http://www.babycenter.com/6_your-pregnancy-40-weeks_1129.bc