At 40 weeks, your body is making final preparations for delivery. Your cervix may gradually begin to dilate, but you won't be in active labor until it reaches four centimeters. When you're dilated 10 centimeters, your baby will be ready to appear.
The Braxton Hicks or "practice" contractions you've been having might begin to feel more like the real thing. True contractions last at least 30 seconds, occur regularly and don't go away no matter what. If you're unsure whether or not you're going into labor, call your doctor.
As the baby drops lower -- a process called "lightening" -- you'll feel discomfort in your pelvic area. The bad news is that you'll need to urinate more often. The good news is that you'll be able to breathe more easily and eat without heartburn.
You may lose the mucous plug that has protected your uterus from infection during your pregnancy. The plug is tinged with blood and often called the "bloody show." You might get a little clumsy as your bones, muscles and joints relax and the ligaments of your pelvis loosen to enable it to open during birth. The cause is relaxin, a hormone produced by your placenta.