The nerves cells in your baby's brain are developing their sense of sight, sound, taste, touch, and smell. And inside your little one's lungs, the main airways (called bronchioles) are beginning to form.

Your little one is also kicking around more this week. They now have hair sprouting from their scalp and lanugo, a furry smattering of hair all over the body. Unlike vernix caseosa (the white, creamy protective layer covering the skin) lanugo usually disappears by birth. The only exception is with a premature delivery.

If you're having a girl, her uterus and fallopian tubes are developed and identifiable. If you're having a boy, his testes and penis are developed and identifiable. If you don't wish to know the sex of your baby, be sure to make that clear with the ultrasound technician before your next ultrasound to avoid any unwanted information!

You may finally feel entirely pregnant... and people can probably tell you are, too! Your uterus has outgrown your pelvis, and you might feel a little discomfort in your lower belly. This round ligament pain is caused by your muscles stretching to house your growing baby. Don't worry too much about this discomfort, and you should for sure tell your midwife or doctor about any pain or discomfort, always, during pregnancy.

Speaking of pain, if your legs are cramping in the middle of the night, compression socks might be your next favorite thing. Many pregnant women go through this and lose out on a good night's sleep because of it. Stretching your legs - specifically your calves, but also your thighs, quads, knees, ankles, and toes - right before you get in bed at night may help in reducing these cramp-waking sleep disturbances.

This week, your skin could feel itchy, dry, or flaky. You might be sporting a gorgeous linea nigra. You could even wake up one morning and recognize the mask of pregnancy (blotchy patches on your forehead, cheeks, nose, and/or chin). These hormone-related skin changes should gradually disappear after childbirth and in the meantime, just continue to drink a lot of water and eat a healthy, balanced diet. Now that you're well in to the second trimester, you should be gaining about one-pound per week.

As your body grows to make more room for your little one, it also produces more blood to support all systems on go. This extra blood flow can lower your blood pressure, so if you stand up too quickly, you might feel dizzy or lightheaded. This is called postural hypotension and is just one more way your body is reminding you to slow down.

Dizziness is also sometimes caused by the pressure of your uterus on the aorta and vena cava (two large vessels supplying blood to your body). When these vessels are compressed under your growing uterus, the speed at which blood circulates throughout your body slows, causing hypotension. Typically, you can relieve this symptom by lying on your side (it doesn't matter which side). Once you're flat on your side, the pressure of your uterus on the aorta and vena cava releases, allowing a healthier, more normal speed of blood flow circulation to resume.