This week, your little one’s facial features finally look like "my parents are human." The eyes are at the front of the face, and both ears have settled into their proper side positions. More notably, your baby's reflexes have begun! That little mouth is making even littler sucking motions. And eye muscles are clenching, toes are curling, and fingers and hands are opening and closing. Your baby might even be sucking on a thumb, right now. It's still too soon for you to feel any movements, but your baby can feel you. If you applied pressure to your abdomen, your baby would squirm in response!

During week 12, your baby's brain is also rapidly developing. Nerve cells are multiplying, and the small junctions across which nerve impulses pass from one nerve cell to another, called synapses, are forming at an impressive speed.

Your little one's intestines are developing too, and soon will move into the stomach cavity. It's incredible to think of how far your baby has come in just a few short months!

By week 12, you may notice some skin changes, such as darker freckles or more freckles. You may even notice a dark line, about a centimeter across, running vertically down your stomach. This line is called the Linea Nigra (Latin for "black line"). If you develop a linea nigra, here's a fun, old wives' tale associated with it: if the linea nigra runs to the navel, it's a girl; but if it goes all the way up to the bottom of your sternum, you will have a boy!

These changes in skin pigmentation are caused by pregnancy hormones, increasing the production of the pigment melanin. Women with darker pigmentation are more likely to develop the linea nigra line than women with fair skin. Among the women who do develop this line, it reportedly disappears a few months after birth.

During week 12, many women begin to experience heartburn. If you experienced it before pregnancy, it may be even worse now. Again, you may blame your hormones. Increases in the progesterone hormone produced by the placenta cause the valves separating the esophagus from the stomach to relax, allowing gastric acid to sneak back up the pipe and ultimately cause you that uncomfortable burning sensation. Some tips to manage your heartburn include:

• Staying upright. Try to sit up for at least 30 minutes before bed. At bedtime, place a folded towel or extra pillow under your mattress to elevate your head above your stomach while you sleep. At bedtime, place a folded towel or extra pillow under your mattress, elevating your head above your stomach while you sleep
• Sipping drinks slowly. Don't gulp, no matter how thirsty you are. Also try to avoid drinking with meals, as this increases the volume of your stomach
• Avoiding big meals before bedtime. In fact, try grazing through smaller meals during the day
• Keeping away from problematic foods, like carbonated beverages and greasy meals

If you've been suffering from morning sickness and exhaustion, by week 12 your nausea should begin to recede. You may even feel more energetic and motivated. If you want to get back to exercising, now that you are feeling better, it is a great time to check out some of the local prenatal yoga classes, or to walking with friends in the evenings. You can also start to relax a bit, as your risk of miscarriage drops significantly after the twelfth week.