This week your baby measures over 16 inches long. He weighs about 3 1/3 pounds and is heading into a growth spurt. He can turn his head from side to side, and his arms, legs, and body are beginning to plump out as needed fat accumulates underneath his skin. He's probably moving a lot, too, so you may have trouble sleeping because your baby's kicks and somersaults keep you up. Take comfort: All this moving is a sign that your baby is active and healthy.
Have you noticed the muscles in your uterus tightening now and then? Many women feel these random contractions in the second half of pregnancy. Often lasting about 30 seconds, they're irregular, and at this point, they should be infrequent and painless.
Frequent contractions, on the other hand even those that don't hurt may be a sign of preterm labor. Call your practitioner immediately if you have more than four contractions in an hour or any other signs of preterm labor: an increase in vaginal discharge or a change in the type of discharge (if it becomes watery, mucus-like, or bloody, even if it's pink or just tinged with blood); abdominal pain or menstrual-like cramping; an increase in pressure in the pelvic area; or low back pain, especially if you didn't have it before.
You may have noticed some leaking of "premilk," from your breasts lately. If so, try tucking some nursing pads into your bra to protect your clothes. (And if not, it's certainly nothing to worry about; if your current bra is too snug, you might also want to pick up a nursing bra. Choose a nursing bra at least one cup size bigger than you need now. When your milk comes in you'll be grateful for that extra room!