Your Weekly Pregnancy Development: Week 39

Your baby gets antibodies from the placenta to protect her against illness

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Your baby probably weighs anywhere from 6 to 9 pounds.

The countdown begins

Week 39: Your baby is storing antibodies as delivery nears

When you're 39 weeks pregnant, your baby is making final preparations for her arrival:

  • The waxy vernix covering her skin and the fine hair called lanugo will be nearly gone when you're 39 weeks pregnant. However, some vernix and lanugo might remain at birth.
  • Your baby gets antibodies from the placenta to protect her against illness.
  • She also will get more antibodies if you breastfeed her at birth.
  • Your baby probably weighs between 7 and 7-1/2 pounds, but it's normal for her to weigh anywhere from 6 to 9 pounds.


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Your Week 39 nutrition and health

Preparing for breastfeeding

When you're 39 weeks pregnant, your body makes final preparations for your baby's first meal.

  • Your breasts reach their full size. They might enlarge again after delivery until your milk comes in.
  • Your breasts might begin to leak a thick, yellowish milk. This is colostrum. It is packed with nutrients and antibodies to help give your baby a great start.


Plan ahead for your mealtimes

If you are planning to breastfeed, it is more important than ever to be vigilant with your diet. Vitamin D in particular is a nutrient known to be deficient in breast milk. Supplements are needed for your baby to get the 400 IU per day recommended by the AAP.

Important nutrition tips for lactating moms include:

  • Continue to eat from the five food groups. Lactating moms can get a food plan of their own at
  • Be sure to get 1000 mg of calcium a day.
  • Drink approximately 13 cups of water and other beverages per day.

Here’s an easy way to make sure you are getting the nutrients you and your baby need for breastfeeding: Before your baby arrives, try to plan ahead for nutritious meals after she arrives home. If you can, cook and freeze a few simple meals that you quickly can reheat in the oven or microwave. Stock up on nutritious foods and snacks to make mealtime easier with a newborn in the house.


Pregnancy Weeks images

Are these real contractions?

When you're 39 weeks pregnant, contractions could be the real thing. Learn more about contractions so you can distinguish the real ones from the false ones.

  • Contractions occur when the uterus tightens and relaxes.
  • Some contractions are called Braxton-Hicks contractions. These contractions are called false labor, and they help your body practice for the real thing.
  • In most women, uterine contractions get closer together, become more intense, and last longer as childbirth approaches.
  • Sometimes contractions stop altogether.
  • You can use a stopwatch or clock to time the contractions when they start. Call your doctor when they occur closer together, intensify, or last longer.
  • During a contraction, you will feel pressure and pain in your lower back and abdomen.
  • Your abdomen will tighten.
  • Between contractions, your abdomen and uterus will relax.
  • Contractions help your baby travel through the vagina.
Keep learning about your baby's development every week
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