Your Pregnancy Week 18

Reviewed by James Brann, MD
Learn about your symptoms and changes during the 18th week of pregnancy.

Your Baby

During pregnancy week 18 your baby may be between five to six inches long already and weigh more than 5 ounces!

Changes in Your Growing Baby

Your baby is busy building a strong heart and strong muscles. An ultrasound now can usually help detect any structural problems that may exist in the heart or surrounding organs. Some babies do have congenital heart defects, though most will be born with no problems at all. Fortunately if an ultrasound does detect that something is awry you can take steps to prepare ahead of time to support your newborn baby after birth.
By now your baby is producing Myelin, a protective covering that supports the nerves in your baby's body. Your baby will continue to produce Myelin through the ninth month.

By now your babies genitals are also formed and can be distinguished using an ultrasound. Most women will have to wait until roughly their 20th week of pregnancy, to find out the gender of their baby.

Your Body's Development

You can probably feel your uterus just at or just below your navel. If you are having trouble differentiating your uterus from the rest of your belly don't worry. Your doctor is skilled in detecting subtle changes and the size and shape of your uterus, and may even allow you to feel your uterus along with them. You definitely have a little tummy to show off and may have gained up to 15 pounds by now.

Changes in Your Body

As you start to grow and expand as you continue your pregnancy you may find that you start getting a bit uncomfortable. Most women realize some discomfort as they try to get a good nights sleep at night. One thing you can do to improve your comfort is invest in a good pregnancy pillow, one that can support your expanding uterus and belly. You may want to lie on your left side when sleeping. This can help prevent compression of your inferior vena cava, a large vein in the body supplying blood back to your heart.

Soon you will be undergoing an ultrasound. Typically most health care providers offer an ultrasound between 18 and 20 weeks pregnant. This ultrasound ensures that your baby is developing properly and helps your doctor identify any birth defects or potential problems. Your doctor will check your baby's size, the position of the placenta and the umbilical cord and re-estimate your baby's due date to make sure your original estimates are accurate.

You may want to schedule your ultrasound on a day your partner can join you. This is often the first time many new parents will catch a good glimpse of their baby. Most ultrasounds last up to 30 minutes. That's a good amount of time for you and your partner to bond with your little baby.

At 18 weeks pregnant you can usually find out the gender of your baby. Many parents anxiously await this news so they can plan their nursery, while others prefer a surprise at birth. Either decision is terrific. You should always opt for what makes you most comfortable. Keep in mind that while usually very accurate, sometimes an ultrasound may be off. There have been cases where a technician decided the baby was a girl and on birth the family found out they were having a little boy! Keep this in mind when making future plans for your baby.

Physical Changes

In addition to your growing belly bump, there are several pleasant surprises of being pregnant. You can blame your pregnancy hormones on many of your aches and discomforts - including backaches, leg achiness, and more. But pregnancy hormones also contribute to other physical changes that aren't so bad.

For one, you may get a luxurious head of hair when pregnant. You may notice that your hair looks healthier and fuller. While you're not growing more hair, you're losing less hair. So it looks like you have more volume. Not a bad perk, eh?

Another physical change you may notice at 18 weeks pregnant is faster-growing nails. For once in your life, you might actually have long fingernails that you can paint. Real fingernails that is. You can thank your pregnancy hormones for this physical change.

What some women love about being pregnant is their growing bosom. During pregnancy, it's not unusual for women to go up one whole bra size - or two. For a smaller breasted woman, this is a welcome change. They actually have cleavage now.

With all these physical changes, you may notice that your partner is more in love with your physique than ever. Men typically love the sensuality associated with soft curves and growing breasts.

Enjoy all these physical changes while they last.

Video: What to Expect from the 18th Week of Pregnancy



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