Week 18 of Pregnancy
Second trimester
For informational purposes only. This page is not medical advice. Every pregnancy is different — always consult your doctor, midwife, or healthcare provider for guidance specific to your situation. In an emergency, call your provider or 911 immediately.
Baby is
about the size of a sweet potato
5.5 inches · 5.3 oz
Baby this week
- •Ears are now in their final position on the sides of the head
- •Baby can hear sounds, including your voice and heartbeat
- •Vernix caseosa (protective coating) is beginning to form on skin
- •Myelin sheath is developing around nerves for better signal transmission
- •Baby's movements are becoming more coordinated and recognizable
You this week
- •Increased appetite as metabolism shifts to support baby
- •Occasional lightheadedness or dizziness from blood pressure changes
- •Vivid dreams (often intensified by hormonal changes)
- •Back or pelvic discomfort as your center of gravity shifts
- •Possible increased vaginal discharge
- •Growing belly may make finding comfortable sleeping positions harder
This week's tips
- •Start paying attention to your baby's movement patterns so you'll recognize if something changes later
- •Invest in a pregnancy pillow or use regular pillows to support your growing belly while sleeping
- •Schedule your mid-pregnancy ultrasound if you haven't already—it's often the most memorable scan
- •Continue prenatal vitamins and stay hydrated; your blood volume is expanding significantly
- •Wear supportive, flat shoes to help with balance and reduce back strain
- •Practice good posture when sitting and standing to ease back discomfort
Informational only — always check with your doctor or midwife for advice specific to you and your baby.
Looking ahead
You're nearing the end of your second trimester, and many pregnant people report feeling their best during these weeks. The mid-pregnancy ultrasound around now can provide detailed views of baby's development and is a wonderful bonding moment for many families.
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For informational purposes only. This page is not medical advice. Every pregnancy is different — always consult your doctor, midwife, or healthcare provider for guidance specific to your situation. In an emergency, call your provider or 911 immediately.
This content is for informational purposes only and is not medical advice. Every pregnancy and baby is different. Always consult your doctor, midwife, or pediatrician for guidance specific to your situation.
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