Your Guide to Being 18 Weeks Pregnant

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Your Pregnancy at 18 Weeks: What's Happening in There?

Your Pregnancy at 18 Weeks: What's Happening in There?

A new development may fuel more movement from your baby.

Mom Tip at 18 Weeks Pregnant

Did you know...?

Your baby's bones will begin to harden this week. Continue to take your prenatal dietary supplement with brain-nourishing docosahexaenoic acid (DHA) and eat calcium-rich foods. That calcium will help your baby’s bones become firm; it also aids in muscle contraction, blood clotting, and nerve transmission.

Your Baby at 18 Weeks Pregnant

Pregnancy at 18 Weeks: What's Happening in There

Your baby measures five and a half inches from crown to rump (from the top of her head to her bottom) and weighs about 7 ounces when you're 18 weeks pregnant.
She is about to start hearing sounds. Your baby’s ears are now situated on the sides of her head, her nerve endings are developing, and the bone in her inner ear is forming. Together these elements allow your baby to hear the beat of your heart, the workings of your digestion, and the movement of blood through her umbilical cord.
She is moving more. Those gains in hearing mean that your baby may be startled by loud noises, inspiring her to move or kick. You can feel movement when the baby has hiccups as well.
Her bones are hardening. When you're 18 weeks pregnant, your baby’s bones are starting to change from a soft substance to a strong, hard structure. This process, called ossification, usually begins in her clavicles (collarbones) and legs.
Her fingerprints are forming. These one-of-a-kind whorls began forming around week 12 and are continuing to develop on her fingers (and toes) during week 18.

Baby Brain Waves

Your Baby’s Brain Is Developing

The nerve cells (neurons) in your little one’s brain are forming at a rapid pace; in fact, 100 billion of them will be created in the first five months of pregnancy. Connections, or synapses, between these neurons are also forming in the spinal cord and brain stem, helping to refine your baby’s movements, reflexes, and senses.