18 Weeks Pregnant

Here's what's happening during Week 18 of your pregnancy.

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Your Growing Baby:

Fat is being deposited throughout the body. Teeth have started to form. The fetus begins to hear sounds in your body (such as your heart beating) and may even startle at loud noises. Length: about 8 inches; weight: 6 ounces

There's still plenty of room in your uterus, so your fetus can be quite active with her new muscles. She may change positions frequently, cross her legs, recline, suck her thumb, and turn somersaults. Her retinas have become light sensitive, and your baby may be able to detect a glow if you shine bright lights at your belly (even though her eyelids are sealed).

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Your Growing Belly:

During this week, and the next few weeks, you may feel your baby's first movements—a fluttery sensation in your pelvis. Called "quickening", many cultures believe that this is when life begins. You may have aches and pains in your legs, tailbone, and other muscles.

Tips & To-Do's:


Decide whether or not you'd like to know your baby's sex. Many doctors do a detailed ultrasound between 16 and 20 weeks, at which time gender often can be determined.


WHEN IT'S OFFERED: At about 20 weeks.

WHAT IT SCREENS FOR: A wide variety of problems. "An anatomical survey of the entire fetus is typically conducted," explains midwife Barbara McFarlin.

HOW IT WORKS: Using a transducer placed over the abdomen, sound waves create pictures of the fetus.

HOW EFFECTIVE IT IS: McFarlin says it detects approximately 50 percent of heart defects; O'Brien says it's excellent at detecting NTDs. However, O'Brien adds: "Fifty percent of babies born with Down syndrome had normal ultrasound results."

WHAT IF ...? If ultrasound does detect a potential problem, you'll need to decide if you want an amnio to determine whether it could be part of a chromosomal or genetic syndrome.

Here's an in-depth look at the screening and diagnostic tests you might undergo.

Things to think about this week

If you have certain pregnancy complications or limitations or if you just want to play the pregnancy card! You might need to cross these household tasks off your to-do list and either delegate them to someone else or hire some help.

NEW:  Listen to Our Week-by-Week Podcast All About Your Pregnancy 

Each episode of the new Pregnancy Confidential podcast, hosted by our editors, walks listeners through the physical, emotional and all-round quirks of each week of pregnancy. This is real-talk, girlfriend-to-girlfriend stuff—no hard-to-understand medical information here—taking you through the real feelings of pregnancy so you're never alone. And it'll have you chuckling all along the way. All episodes available now!