Week 31 Pregnancy: Cramps, Baby Position & Symptoms

week 31 pregnancy cramps, baby position & symptoms

You’ve reached week 31 of your pregnancy — 29 weeks from when your baby was conceived. Let’s talk about baby’s development and position, and about cramps and other pregnancy symptoms at week 31.

Estimated reading time: 6 minutes

Week 31 Pregnancy: Baby Bump

At week 31, your baby weighs about 3 1/3 pounds. Her total length is now nearly 16 inches.

Your belly is continuing to grow, too! The uterus now fills a large part of your abdomen. The top of it rests about 4 1/4 inches from your belly button, meaning that the fundal height is just over 12 inches from the pubic symphysis. Depending on your prepregnancy weight and how you’ve gained along the way, your total pregnancy weight gain is likely between 21 and 27 pounds (2).

week 31 pregnancy baby bump

Baby’s Development

Baby is growing in leaps and bounds now, and making the following big changes:

  • Baby is adding body fat
  • Very active
  • Breathing movements are present
  • Baby responds to sound
week 31 pregnancy baby development

Week 31 Pregnancy: Baby Position

By around week 29 or 30, it is normal for baby to be either vertex (head down) or breech (any position other than the head lying over the cervix.) The head-down position is ideal for vaginal birth. Due to increased risk to your baby, providers encourage a cesarean birth rather than vaginal if baby is in a breech position at the time of delivery.

During your prenatal visits, your provider may try to determine baby’s position by feeling your abdomen. This is a technique known as Leopold maneuvers. Ultrasounds are the only definitive way to assess baby’s position. However, Leopold maneuvers performed by experienced providers are considered an effective way to help screen for the breech position (4).

What if Baby is Breech?

As your pregnancy continues, baby has less and less space to move within the uterus. The later in pregnancy a baby is breech, the more difficult it can become for baby to flip to a head-down position. If your baby is in a breech position at week 30, encourage baby to turn by practicing good posture and by exercising/walking regularly (5). A qualified chiropractor may be able to adjust your pelvis and encourage baby to move into a head-down position. Sometimes an external cephalic version can be performed to try and turn baby to a head-down position. This is a procedure where an attempt is made to turn baby by gently cupping her head and bottom from the outside of your abdomen and rolling her forward. (That may sound simple, but it should only be done by a trained medical professional in a hospital setting. They monitor baby during the procedure to be sure that she isn’t under any distress.)

Ultimately, though, it’s too early to be too concerned about baby’s position. Even if she is breech at week 31 of pregnancy, she very well may be head-down by delivery time. In fact, only 3 – 4% of babies will be breech at full term.

week 31 pregnancy baby postion

Week 31 Pregnancy: Symptoms

Leg Cramps

Many a pregnant woman has been awoken from a sound sleep by cramps in her lower legs, especially the calf. These leg cramps are typically sharp and painful, and can be brought on suddenly by simply extending your foot. While it’s often suggested that cramps are due to a deficiency in calcium or potassium, the exact cause of leg cramps remains unknown (1).

If leg cramps are a problem for you, consider the following suggestions:

  • Stretch your legs before you go to bed
  • Massage the calf or tense muscle in long, downward strokes (3)
  • Avoid freaking out when you awake with a leg cramp. Instead, relax and flex your foot. This tends to bring immediate relief. Leg cramps offer the perfect opportunity to practice the relaxation techniques you’re learning in your natural childbirth class!
  • If massaging the muscle doesn’t help, simply get out of bed. Standing is almost always an instant fix for a leg cramp, and if it doesn’t stop it right away, walking or stretching the muscle while standing with weight on that leg should do the trick.
week 31 pregnancy leg cramps

Back Ache

You may find that your bach aches by the end of the day now. This is a common complaint in the third trimester. As your bump grows, it puts your center of gravity out front and pulls on your lower back. On top of that, your hormones have caused all the ligaments in your body to relax, so everything is less stable and not working together in quite the way you’re used to.

One of the best ways to help with back pain is to strengthen your core muscles. The muscles in your core can share in maintaining your posture and making sure that your back isn’t solely responsible for supporting your ever-shifting shape. Beyond core strengthening, you may find that it’s helpful to wear a pregnancy support belt, take some weight off your back by swimming a few times a week, and making sure your back is appropriately supported when you sleep. You can find more sleep tips in Kopa Birth’s Tips and Comfortable Sleeping Positions During Pregnancy.

Join us again soon to learn all about week 32 of your pregnancy!

Kopa Birth’s online birthing classes allow you to prepare for natural childbirth in the comfort of your own home, 24/7. Enroll today in our free online childbirth class to learn more about preparing for natural childbirth. 


  1. Ladewig, P.A., London, M.L., Davidson, M.R.  (2006).  Contemporary Maternal-Newborn Nursing Care, 6th edition.  Pearson Prentice Hall. Upper Saddle River, NJ.
  2. Glade, B.C., Schuler, J. (2011). Your Pregnancy Week by Week, 7th edition. First Da Capo Press.
  3. The American College of Obstetricians and Gynecologists. (2010). Your Pregnancy and Childbirth Month to Month, 5th edition.
  4. Lydon-Rochelle, M., Albers, L., Gorwoda, J., Craigh, E., Qualls, C.  (1993). Accuracy of Leopold maneuvers in screening for malpresentaiton: a prospective study. Birth. Sep; 20 (3):132-5.
  5. When is Breech An Issue. Retrieved from https://spinningbabies.com/learn-more/baby-positions/breech/when-is-breech-an-issue/

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Meet Katie Griffin

I’m a registered nurse, Lamaze certified childbirth educator, and the mother of 7. I help women realize their dream of a natural, intimate, and empowering hospital birth.

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You’ve reached week 31 of your pregnancy — 29 weeks from when your baby was conceived. Let’s talk about baby’s development and position, and about cramps and other pregnancy symptoms