Your Baby's Development Your baby now weighs about 2 pounds, 2 ounces (1,000 grams) and measures about 10 inches (25 cm) from crown to rump. The folds and grooves of your baby's brain are still developing and expanding, and your baby's adding layers of fat. At your next prenatal appointment, your health care provider may tell you whether your baby is headfirst or feet- or bottom-first (called breech position) in the womb. Babies who are in the breech position may need to be delivered by C-section. Your baby still has 2 months to change position, though, so don't worry if your baby is in the breech position right now. Most babies will switch positions on their own. Your Body Your health care provider probably sent you for some blood tests early in your pregnancy. One thing blood tests measure is the Rh factor, a substance found in the red blood cells of most people. If you don't have it (if you're Rh negative) but your baby does (is Rh positive), there's the potential for your baby to have health problems, such as jaundice and anemia. Your doctor can prevent these problems by giving you Rh immune globulin shots this week and again after delivery. 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.