39 Weeks pregnant: Baby development, symptoms and signs

Your body at week 39

Baby kicks

Your baby will stay active all the way up until they are born, so you should still be feeling their movements as frequently as ever. You might experience different kinds of movement, though, as your baby is taking up more and more room in your uterus. There is no set number of movements to expect and at this stage of pregnancy, you’re probably pretty familiar with your baby’s movements [1]! However, if you notice a decrease in their activity, contact your midwife or doctor right away. 

Diarrhea

In the final days or weeks before you give birth, it’s not uncommon to experience diarrhea. Before and during labor, your body produces hormones called prostaglandins, which scientists believe encourage the cervix to soften and the uterus to contract [2]. Surges of prostaglandin are also a regular part of menstruation, helping the uterus contract and release the uterine lining (endometrium) in the form of a bleed during your period. In both menstruation and pregnancy, prostaglandins can have a parallel effect on your bowel movements and cause diarrhea for some women [3].

While prostaglandin plays an important role in labor, and can even be used to artificially induce labor, diarrhea is an unreliable predictor of when labor is beginning or how quickly it will proceed [2]. For that reason, while it’s common to have diarrhea before labor, it shouldn’t be considered an early labor sign nor an indication that labor is going to start soon.

Pelvic pain

You might, unfortunately, already be familiar with pelvic pain, or pelvic girdle pain, which can get stronger at the end of your pregnancy. As your baby gets into the birthing position, they press down on your pelvis, which can lead to worsening pain in your pubic region, lower back, hips, groin, thighs, or even knees [4]. This can make moving, walking, sleeping, or doing everyday activities painful and difficult. 

Try to remember to maintain good posture, with a neutral spine and bottom tucked slightly under you, when sitting and standing. Poor posture can make pelvic pain worse. Light exercise (if safe to do in your pregnancy), rest, not staying in any position too long, and using a pillow between your knees when resting or sleeping can all help with pelvic pain [4]. If your pain is becoming worse or affecting your ability to go about your day-to-day life, contact your healthcare provider to see if physiotherapy or other therapeutics might be right for you.

You might be wondering how pelvic pain will affect labor and birth. In most cases, women who suffer from pelvic pain in pregnancy can still have a vaginal birth [4]. However, make sure that your midwife and/or doctor are aware of your pelvic pain so they can help you find a comfortable position during labor and childbirth. 

Changes to your cervix

In your final checkups before birth, your nurse, midwife or doctor might examine your cervix to see whether it has begun “ripening” or effacement, which are words that both mean getting ready for labor. When this happens, your cervix will soften, and get thinner and/or shorter. If this is your first birth, your cervix will also start to open, or dilate, after effacement begins [5]. 

While these changes show that your body is getting ready, they cannot actually predict when labor will begin. Some women experience symptoms of effacement weeks before they give birth. Similarly, labor can proceed so quickly that sometimes your doctor or healthcare provider won’t notice changes to your cervix before your water breaks or you begin having contractions.

Your baby’s development at 39 weeks 

At 39 weeks, your baby is fully developed and is still gaining weight! This extra fat will help them regulate their body temperature and stay warm outside the cozy uterus [6]. At term, your baby can have a firm grasp, so they will be able to hold your finger. They can also turn their head and face you, or a sound. But their eyesight is still developing — at birth, full term newborns can only see about 6-10 inches (15-25 cm) in front of their face. 

This week, your baby likely weighs between 6.5 and 8 lbs (2.9 to 3.6 kilograms) and is around 18 to 20.5 inches (45.7 to 52 cm) long [7]!

Signs of labor at 39 weeks

There are three main signs of labor: contractions, the release of the mucus inside your cervix, and your water breaking. 

• Labor contractions will come at regular intervals that you can time with a watch, and they will get stronger and closer together as labor progresses. These are different from Braxton Hicks contractions, which can come randomly and go away completely. 
• Discharging your mucus plug, which is also known as a “show” or “bloody show”, might be different from the discharge you have been experiencing. It’s usually thick, clear, and can have blood in it [8]. You might not even notice if you lose your mucus plug or you might not lose it until you’re already in labor. 
• Water breaking, which is also called the rupture of membranes, is when the amniotic sack that has been holding the baby opens and the amniotic fluid comes out of your vagina. This can happen in a large rush, or it can leak out slowly. 

You might be wondering, can you be in labor without having contractions or experiencing your water breaking? Despite what you might have seen in movies or on TV, most women won’t experience their water breaking at the very start of labor. In fact, it’s the first sign of labor for only 8-12% of women [9,10]. Contractions, on the other hand, are felt by everyone during labor. Keep track of the frequency of your contractions and follow the guidelines of your hospital or birthing center to know when to contact your midwife or doctor and go to the hospital. Labor can progress unexpectedly, so it’s advisable to be ready to go to the hospital as soon as you begin having regular contractions.

If your water breaks or you suspect you’re leaking amniotic fluid, even if you aren’t experiencing contractions, you need to contact your hospital or maternity clinic immediately. You should also contact them if you experience bleeding of any kind.

Tips in week 39

• Take it easy: first and foremost, try to rest and relax as much as you can this week. Whether you’re giving birth to your first child, or your tenth, your life will be changing a lot as soon as your baby is born. Try to take as much time for yourself, for you and your partner, and for you and your family as possible.
• Stock up on entertainment: being prepared with reading materials, like books or magazines, or having some shows or podcasts downloaded and ready on your phone or tablet can help you relax leading up to and through the early stages of labor, which can sometimes take a long time!
• Consider taking a trip to the pool: at 39 weeks, you might be feeling very large, heavy, and uncomfortable. Not to mention hot! Why not consider a trip to the local pool? If it’s safe to do in your pregnancy, floating, light swimming, or water walking can help take some pressure off your joints and provide some relief for pregnancy aches and pains.
• Prepare for postpartum: labor is hard work, and your body will take time to heal and recover afterward. Whether you have a vaginal birth or caesarian section, you will likely need some extra supplies after giving birth, like maxi pads, postpartum underwear, and peri bottles to help make you as comfortable as possible. Though unpleasant, hemorrhoids are also very common after giving birth, so have some medication or remedies ready just in case.
• Schedule your week 40 checkup: you will most likely see your doctor or midwife at week 40. That appointment is a great time to ask any last-minute questions about labor and birth, so if you haven’t already done so, read up on the delivery process. You can also ask about what happens if your pregnancy goes past week 40 and find out more about induction. 

Support through your pregnancy and postpartum with Natural Cycles

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