2nd trimester: Week 27

The baby's skin is wrinkled, though he's beginning to fill out with fat.

Your Baby

At 13 weeks from birth, your baby is now almost 14 inches from head to toe and tips the scales at a little more than two pounds. He's bulking up with fat to keep him warm after he's born, and his lungs continue to develop. His immune system is also gearing up for life outside the womb. He has discovered thumb sucking, which isn't such a bad thing in the womb--it helps strengthen his cheek and jaw.

Your Body

Lately, you may be feeling your uterus tighten and clench for as long as two minutes. The sensations shouldn't be painful, but they can cause real discomfort. They're called Braxton-Hicks contractions, which many women mistake for labor. Look on the bright side: In addition to giving you a hint of what actual contractions feel like (though in labor they're a lot stronger), they also serve to prepare the uterus for delivery.

Do's and Don'ts

Do keep a journal if mood swings leave you feeling exhausted and confused--writing can help you get a handle on your emotions, which, due to fluctuating hormone levels, might switch from joy to anxiety to excitement at any given time. Your body is morphing in ways you can't control, and so is your life. It's enough to unnerve any mom-to-be.

Health

Recent studies show that only minute amounts of hair dye seep through the scalp and enter the bloodstream, so some experts are green-lighting the procedure for women beyond their first trimester. If you are in the habit of coloring your hair, ask your doctor or midwife about second- and third-trimester touch-ups.

Mom to Mom

If your mood at work swings wilder than a pendulum, give yourself a time-out. "Closing my office door when I knew I would snap helped me. People came in only if they had something really important to discuss."--Denelle Swaim, West Palm Beach, FL