Welcome To Week 18:

Your Baby: Did You Hear A Hiccup?:

At about 5 1/2 inches (14 cm) in length and up to 7 ounces (200 g) in weight, the fetus is growing fast and looking more and more babyish. During this week, your baby sense of hearing has become much more acute. The baby can hear noises within the uterus of your bowel moving and even the blood pumping within your vessels. Additionally, the baby can hear things outside the uterus. So if you are talking to your partner, the baby is hearing some sound. (You may even feel the baby get startled inside from noises that take place outside!)

Though you probably won't feel them at this early date, your baby may have the hiccups, which happens before fetal breathing movements become common.

Your Body: Undergoing An Ultrasound:

If you're like most women, you'll have a routine ultrasound about now so your caregiver can get information on your baby's health. Though this brief (5 to 10 minutes) and painless test is most often done during the second trimester, it can be performed any time between the fifth week of gestation and delivery.

There are two types of ultrasounds: transvaginal and transabdominal. With both, you lie on your back on an exam table while your belly or a probe is lubed up with a special gel. A transducer (a small microphone-like device) is gently pressed on your belly or inserted into your vagina -- the method depends on how far along you are and what type of equipment is on hand. The transabdominal transducer is moved over your belly and it works by picking up the sound waves that come off the bones and tissues in the body at a higher frequency than we can hear. These sound waves then produce an image on a nearby computer screen. The image on the screen, which for some is crystal clear and for others a big blur, is your baby. Regardless, most expectant moms find this first glimpse thrilling -- and over all too quickly.

Ultrasound is a non-invasive test that provides a tremendous amount of information to your health care provider about your baby's development and health. Some of the things that can be seen by ultrasound include:

• Determine an accurate gestational age of the baby
• Determine sex of the baby
• See any anatomical abnormalities that exist in the baby
• Determine if it is just one baby or more than one
• See the location of the placenta and the baby's position within the uterus
• See the amount of amniotic fluid
• Watch how the baby's heart is beating

On That Note: Baby On View:

As your next -- or in some cases, your only -- ultrasound draws near, you're eager to get a look at the precious cargo you're carrying. For a sneak preview of what the test entails, click on this ultrasound presentation.

Weekly Tip:

Wear loose-fitting separates for the ultrasound exam. That way, you can easily pull the top half up and the bottom half down. And even though you'll mop up the goop on your belly with a towel when it's all over, some of it will surely wind up on your clothes. So whatever you do, don't wear your Sunday best!