Welcome to week 18. 22 weeks to go!

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Baby

Your pear-sized baby is growing to about the size of a bell pepper this week. At week 18, your baby is 8.7 inches (22 cm) long and weighs 7.9 ounces (223 grams).

Your baby’s nervous system is rapidly maturing at 18 weeks. A substance called myelin covers nerves which helps speed messages between nerve cells, forming more complex connections. Your baby’s brain nerves are specializing in serving the senses of touch, taste, smell, sight, and hearing. As their retinas develop, they get better at detecting light.

Their skeleton is changing from soft cartilage to hard bones. The umbilical cord, which connects them to the placenta, is growing stronger and thicker. Your baby can move their joints, their sweat glands are starting to develop, and they are yawning.

Talk to your baby. Tiny bones in their ears are in place so that they can hear your voice and other noises outside the womb. When they are born and hear your voice, they will recognize it. Talk to that little one and tell them how excited you are to meet them. See this episode for more information on bonding with your baby during pregnancy.

Mom

Your uterus is about the size of a cantaloupe and has reached just beneath your belly button. You can use your hands to gently feel around and see if you can detect your uterus’s top (fundus).

If you get outside and enjoy some sun, your baby will see a red glow in your belly. It is estimated that 90% of our vitamin D comes from the sun. A study that examined vitamin D deficiency during pregnancy found that 97% percent of Blacks, 81% of Hispanics, and 67% of Caucasians were deficient. Listen to this episode for more in-depth information on sun exposure during pregnancy.

It is routine for expecting moms to get an ultrasound anatomy scan in the second trimester. Generally, you can expect to have this done at 18-20 weeks. This ultrasound diagnoses fetal malformation and structural abnormalities, confirms a multiples (twins) pregnancy, verifies dates and growth, identifies excessive or reduced levels of amniotic fluid, and evaluates your baby’s well-being. During this ultrasound appointment, the professional performing the ultrasound will measure your baby’s height, around their middle, and head circumference. Since this is an anatomy scan, the ultrasound technician will look at the heart’s four chambers, the kidneys, bladder, stomach, brain, spine, and sex organs. You can learn more about ultrasounds in this episode.

Tip for Dads and Partners

Make it a priority to attend prenatal appointments. This allows you to be included, have input in any major medical decisions, ask questions, and hear everything firsthand. If any complications come up throughout prenatal care or unfavorable test results come back, those appointments can be tough to go through alone. One of the more significant appointments for you to attend this trimester is the anatomy scan ultrasound. You will see a picture of your baby, hear its heartbeat, and find out whether you are having a boy or a girl.

Want more evidence-based information to navigate your pregnancy and birth?

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