Your baby is full term! Week 38 pregnancy marks 36 weeks since your baby was conceived, and as many as 30 or so weeks that you’ve known this little one was coming. You may be waiting for few more weeks, or you could be holding your baby tomorrow. What an exciting time! Let’s talk about symptoms, the possibility that you’re walking around dilated, and signs of labor.
Week 38 Pregnancy: A Look Inside
Your little one probably weighs in at around 6 3/4 pounds. He or she is about 14 inches from crown to rump, or 19 2/3 inches from crown to heel (1). What else is going on with baby?
- He or she continues to gain weight, storing fat that will help with body temperature regulation. (And really, what is cuter than baby chub?)
- Lungs continue to mature. Cells in the lungs produce chemicals such as surfactant, which are needed for breathing after birth (1).
- He or she is rapidly storing iron. These stores, along with what he’ll get from breast milk, will meet his needs for the next 6 months (2).
You probably like you’re all belly at this point. The top of your uterus is now 14 1/2 to 15 1/4 inches from the pubic symphysis, and 6 1/2 to 7 1/4 inches above your belly button (1). It may be hard to believe it, but your uterus (just the uterus itself, not baby or anything else) now weighs about 2 1/2 pounds (2). For reference, it was about 2 ounces before you were pregnant! Isn’t your body incredible?!
Week 38 Pregnancy: Symptoms
We’ve talked about contractions the last couple of weeks, but it’s worth mentioning again. No talk of late pregnancy symptoms is complete without mentioning the contractions that you may be feeling with increasing frequency. Your uterus may be contracting more often and more strongly (3). Your contractions may seem to be set off by everything — exercise, a sneeze, bumping your belly, or absolutely nothing at all. Along with your hormones, these contractions are preparing your body for labor.
Before your baby is born, your breasts begin producing colostrum, a highly nutritious fluid that’s your baby’s first milk (2). Colostrum is a thick yellow fluid. It contains proteins and antibodies that help boost baby’s immune system. And, colostrum gives your baby nourishment until your breasts start making milk a few days after your baby is born (1, 3). You may see colostrum leaking from your breasts, or notice a dry crust on your nipples.
If your breasts leak frequently, consider using nursing pads. These are absorbent circular pads that you place in your bra, and they come in both disposable and washable forms.
Week 38 Pregnancy: 1 cm Dilated
You may have learned from a cervical check at your last prenatal appointment that you are a centimeter or two dilated. What does this mean? Is labor starting? Not necessarily. The start of labor is marked by the presence of regular contractions that bring about continued dilation and effacement. But, it does mean that your body is making progress–that your cervix is beginning to open.
Progress can be very slow, though. Some women progress from a closed cervix to 10 cm in a matter of hours once labor has begun, and others walk around for weeks 1 – 2 cm dilated without any contractions (4). As great as it would be if we could predict things more accurately, we’ll just have to embrace the fact that labor and birth remain one thing in life that are necessarily a surprise. If you’ve begun to dilate at all, just embrace the fact that forward motion is happening.
Week 38 Pregnancy: Signs of Labor
We’ve been talking about signs of labor for a couple weeks, but right now, this information is pretty much the center of your thoughts. As you wait for baby, pay attention to your body’s signals so you’ll know when labor is approaching (5).
Lightening is when baby moves down lower into the pelvis. This is also known as engagement. With baby dropped downward and the uterus no longer pushing into the diaphragm and lungs, breathing often becomes easier. However, it may be traded for leg cramps or pains, increased pelvic pressure, and edema in the legs and feet.
Braxton Hicks Contractions
Braxton Hicks contractions are known as “practice contractions” of the uterus. The muscle tightens, however it doesn’t bring about effacement or dilation of the cervix. While they’re typically painless, Braxton Hicks contractions that have been occurring for some time may become more uncomfortable. They may become strong enough for a woman to believe she is in labor, and this is called false labor.
False labor can be uncomfortable and exhausting, and there’s no way to know if it’s the beginning of true labor unless your cervix is being checked regularly, which is not typically recommended. Call your provider if you’re unsure of what to do, and he or she can help you decide if it’s time to come in.
In the meantime, change up your activity level. If you’ve been standing all day, try lying down. If you’ve been lying down all day, get up and go to walk. Braxton Hicks contractions will usually go away in response to a change in activity level.
The cervix softens before labor begins. As we discussed last week, the labor contractions help to thin (efface) and open (dilate) the cervix. Some women experience cervical changes days or weeks before labor, and for others, the cervical changes happen all at once during labor.
We learned in week 37 pregnancy that the cervix contains a mucus plug during pregnancy. When it comes out, there is often a small amount of blood loss from exposed capillaries in the cervix. This results in pink-tinged secretions known as bloody show.
Rupture of Membranes
In about 12% of women, the water breaks before labor starts. In most cases, labor starts within 24 hours of the membranes rupturing. If labor doesn’t start within 24 hours, your doctor or midwife may talk to you about the possibility of inducing labor. (This is not always necessary; it’s just something that will likely be brought up for discussion if more than a day passes between water breaking and labor starting.)
Sudden Burst of Energy
No one knows exactly why, but some women get a burst of energy a day or two before labor. If you find yourself suddenly full of energy, it may be a sign that labor is close. Try not to overdo it with baby-prepping though (i.e. painting the nursery), as your body will need the energy for labor.
Some women lose up to three pounds due to fluid loss and electrolyte shifts caused by changes in hormones.
Diarrhea, indigestion, or nausea
It isn’t known for sure why, but any or all of these may occur shortly before labor.
1. Glade, B.C., Schuler, J. (2011). Your Pregnancy Week by Week, 7th edition. First Da Capo Press.
2. Simkin, P. (2010). Pregnancy, Childbirth and the Newborn, 4th edition. Meadowbrook Press
3. The American College of Obstetricians and Gynecologists. (2010). Your Pregnancy and Childbirth Month to Month, 5th edition.
4. Fletcher, Jenna. “1-Centimeter Dilated: What It Means and When Will Labor Start?” Medical News Today, MediLexicon International, www.medicalnewstoday.com/articles/322843.php.
5. Ladewig, P., London, M., & Davidson, M. (2006). Contemporary Maternal-Newborn Nursing Care, 6th edition. Pearson Education Inc. Upper Saddle River, NJ.