Your Baby

From crown to rump, your baby measures about 4 1/2 inches, roughly the size of an open palm. He weighs about 3 1/2 ounces, but not for long, as fat is starting to fill out his body and keep him warm. By the time he's born, fat will account for two-thirds of his body weight. He has eyelashes now, although he's months away from being able to bat them.

Your Body
Your uterus is about two inches below your belly button. As it fills the pelvis, it pushes up against your intestines, shifting them aside. Your lower abdomen swells with child, literally inside, the placenta is working hard to support and nourish your baby, its network of blood vessels delivering nutrients and carting away waste.

Do's and Don'ts
Do munch on mini meals. Experts recommend eating six small meals throughout the day instead of three large ones to ease indigestion (caused by pregnancy hormones that slow down the digestion process). This way, you'll also avoid the nausea that kicks in when you go for hours without eating.

Health
Some women suffer migraine headaches for the first time during pregnancy, which doctors chalk up to fluctuating estrogen levels. Unfortunately, you can't rely on medications to make them go away. Instead, head off migraines at the pass by avoiding triggers such as chocolate, MSG, and caffeine. Minimize stress and try to get enough sleep (admittedly, that's easier said than done).

Mom to Mom

Advice from moms in the know: "If your job involves managing clients, let them know as soon as possible that you're expecting and assure them that your temporary replacement will be prepared to take over by the time you go."--Sarah Edwards, mother and coauthor of Working From Home

Shopping
Splurge on pants made especially for pregnant women, outfitted with stretchy front panels. Buying regular pairs in larger sizes may save you money, but they'll probably be too big in the legs or not clingy enough to fit snugly around your waist. Hip brands such as Seven, Gap, Old Navy, and Target have their own maternity lines, too, meaning you don't have to change your style just because you're expecting.

Exercise
Skip exercises that call for you to lie flat on your back. After the fourth or fifth month, the position puts you at risk for compressing a major blood vessel, called the vena cava, and decreasing blood flow to the baby.

Relationships
Spread the joy and update close friends and family members with a mass e-mail after every checkup. They'll be glad to know you're doing well and will feel honored you're involving them in your pregnancy.

Siblings
Give your firstborn a taste of what's to come by arranging to visit a friend's or relative's new baby. If you don't know anyone who has just given birth, head to the bookstore and help him pick out a book about a growing family, such as The New Baby by Mercer Mayer and What to Expect When Mommy's Having a Baby by Heidi Murkoff.

Twins
If you run into parents and caregivers of twins while you're out and about, ask for recommendations on equipment like double strollers and joggers.