Your Baby's Development By this week, the umbilical cord has formed. It will be your baby's connection to you during your pregnancy, providing oxygen and nourishment for your baby and disposing of wastes. Your baby's digestive tract and lungs continue to form. Are you longing to see your baby's face on his or her birth day? You have a long way to go until then, but your baby's face is taking shape. The mouth, nostrils, ears, and eyes are some of the facial features that become more defined this week. Dreaming of a son or daughter to play ball with? The arm bud that developed just last week has a hand on the end of it, which looks like a tiny paddle. Your Body Pregnancy causes many changes in your cervix. By this week you'll have developed a mucus plug, which forms in the opening of the cervical canal and seals off the uterus to protect it from infection. (You'll lose this plug later when your cervix dilates in preparation for labor.) PREGNANCY CALENDAR: A week-by-week guide Previous Next 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 Trimester 1 Trimester 2 Trimester 3 Back to Articles Related Articles Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995-2021 KidsHealth®. All rights reserved. Images provided by The Nemours Foundation, iStock, Getty Images, Veer, Shutterstock, and Clipart.com.