The fetus is starting to put on fat. Until now, the body has been lean and bony, but brown fat is beginning to accumulate under the skin. This fat will be crucial for temperature regulation after birth. The umbilical cord is also growing stronger and thicker.
Your Baby This Week
Size: Pear (about 13 cm, or 5.1 inches)
Weight: About 140 grams
- Fat stores: Brown adipose tissue starts forming. This special fat generates heat and will help the baby stay warm after birth.
- Sweat glands: Developing across the skin
- Umbilical cord: Getting thicker and more durable, with strong blood vessels protected by a jelly-like substance called Wharton's jelly
- Cartilage to bone: The skeleton continues its transformation from soft cartilage to hard bone
- Hearing: Improving. The fetus can hear your heartbeat, digestive sounds, and your voice as a muffled vibration.
- Fingerprints: Fully unique patterns are set by now
The fetus is also practicing sucking and swallowing more frequently, important skills for feeding after birth.
Your Body
- Increased appetite. You may feel hungrier than usual as the baby grows.
- Stretch marks may start to appear on the belly, breasts, hips, or thighs
- Dizziness from changes in blood pressure, especially when standing up quickly
- Heartburn as the growing uterus pushes stomach acid upward
- Vivid dreams continue for many
Your blood volume has increased by about 40% compared to before pregnancy.
What to Do This Week
- Eat omega-3 fatty acids. DHA supports the baby's brain and eye development. Good sources include salmon, sardines, walnuts, and DHA-fortified eggs. If you do not eat fish, consider a DHA supplement.
- Stand up slowly to prevent dizziness from postural hypotension.
- Stay social. The second trimester is often when people feel their best during pregnancy. Enjoy it.
Common Questions
Why am I getting heartburn?
Progesterone relaxes the valve between your stomach and esophagus, allowing acid to flow upward. The growing uterus adds pressure from below. Eating smaller meals, avoiding spicy or fatty foods, and not lying down right after eating can help.
Are stretch marks preventable?
Stretch marks are largely determined by genetics and how quickly your skin stretches. Moisturizing can reduce itching and may help skin elasticity, but no cream has been proven to prevent them completely. They typically fade from red or purple to silvery white over time.