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18 Weeks Pregnant Symptoms and Signs

18 Weeks Pregnant: Your Body Shape Begins to Change

Created: 05/30/2014
Last Updated: 06/11/2014

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Once you hit your 18th week of pregnancy, it may become more difficult to fit into your jeans and to hide the fact that you're expecting. Empire-waist dresses and loose-fitting tops will likely disguise your bump for a while longer, especially if it's your first pregnancy, but your little one is definitely growing and developing.

Tip of the week:
Keep exercising regularly, and don't forget to exercise your pelvic floor muscles by doing Kegel exercises. They'll help you avoid urine leaks during and after pregnancy and may even help you in labor. They also can increase circulation to your genital area, which may help with healing after delivery and can prevent hemorrhoids. To do Kegels, pull in or squeeze your pelvic muscles as if you were trying to stop the flow of urine or keep from passing gas. Count to 10 as you hold the contraction, relax, then repeat. Complete sets of 10, aiming for three or four sets each day.

Your baby is now between 5.5 and 6.5 inches long, roughly the size of a bottle of face cleanser. She's starting to flex her arm and leg muscles, getting ready to give you some hearty kicks to remind you of her presence. She's also learning how to yawn and hiccup, and you may feel sensations from the latter.

Your little one is also probably forming fingerprints, as well as myelin, which is the tissue that covers and protects her nerves. Additionally, her uterus and fallopian tubes are starting to position themselves in the correct spot. (If she is actually a "he," his genitals are now showing, though they may not show up on an ultrasound.)

As all of these important developments occur, your uterus is expanding to where you likely can no longer ignore your bulging belly, though it still may not be obvious to others.

In addition to the outward changes, you may experience some dizziness stemming from low blood pressure. This occurs when you sit up after lying down for a while, because, when you lie on your back, your uterus compresses an artery, slowing your blood flow. When you sit up, the rush of blood can make you feel light-headed.

You may also begin to feel some back pain. This occurs when your shifting center of gravity causes you to lean forward, potentially stressing the spine. In addition, the hormones in your bloodstream are getting your hip joints loosened up for delivery. These chemicals affect other joints as well, so your spine may have a tough time staying straight under the extra weight.

If back pain restricts your daily activities, talk to your health care provider about your options. However, if it's just a mild annoyance, try to stand up straight and lift items using your leg strength. Also, keep your feet up when you're sitting down, and support your lower back with a small pillow.

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