At 38 weeks pregnant, your baby weighs roughly 6.5 pounds, though some babies are already close to 9 pounds by now. You’re in what doctors classify as “early term,” meaning your baby is nearly ready but still putting finishing touches on key organs. Most of what’s happening this week involves your body preparing for labor and your baby’s brain and lungs completing their final development.
How Your Baby Is Developing
Your baby’s brain at 38 weeks is about 90% of its full-term weight, which means significant neural development is still happening right now. The brain is building connections, adding fat layers for insulation around nerves, and refining the systems that will control breathing, temperature regulation, and feeding after birth. This is one reason doctors discourage elective deliveries before 39 weeks: that last stretch of brain growth matters.
Lung development is also wrapping up. The lungs are producing surfactant, a substance that keeps the tiny air sacs from collapsing when your baby takes a first breath. Babies born at 38 weeks generally do well, but respiratory problems are more common compared to those born even one week later. The American College of Obstetricians and Gynecologists notes that the lowest rates of newborn complications occur in uncomplicated pregnancies delivered between 39 and 40 weeks.
Your baby’s size can vary widely at this stage. While 6.5 pounds is a common estimate, some babies weigh nearly 9 pounds or more. Length is typically around 19 to 20 inches. Your baby is also shedding the waxy coating (vernix) that protected the skin in the amniotic fluid, and the fine body hair (lanugo) is mostly gone.
What “Early Term” Means for You
Pregnancies between 37 weeks and 38 weeks, 6 days are classified as early term. This replaced the older practice of calling everything from 37 to 42 weeks simply “term.” The distinction exists because outcomes genuinely differ across those weeks. Quality improvement efforts across hospitals now focus on avoiding non-medically indicated deliveries before 39 weeks, since respiratory issues and other complications drop meaningfully when babies stay put a bit longer.
That said, some conditions make delivery at 38 weeks the safer choice. Chronic placental problems, certain blood pressure conditions, and other complications can shift the risk balance. If your provider recommends induction before 39 weeks, there’s typically a medical reason. If delivery is deferred, it’s because waiting benefits your baby’s development.
Physical Changes You’re Feeling
One of the most noticeable shifts around 38 weeks is “lightening,” when your baby drops lower into your pelvis. This engagement puts the baby’s head closer to your cervix, which increases pressure on the nerves in your lower pelvis. You may feel sharp, shooting pains in your pelvic area, sometimes called lightning crotch. The upside: with the baby sitting lower, you may find it easier to breathe as pressure on your diaphragm eases. The downside: your bladder has even less room, so bathroom trips become more frequent.
Braxton Hicks contractions often intensify this week. These “practice” contractions feel like a tightening across your abdomen and can be uncomfortable, but they’re irregular and don’t progressively get stronger. Other common symptoms include swollen feet and ankles, lower back pain, difficulty sleeping, and general fatigue. Some women also notice increased vaginal discharge or the loss of their mucus plug, which can happen days or weeks before labor starts.
Sleep and Comfort Strategies
Sleeping comfortably at 38 weeks is a genuine challenge. Side sleeping is the recommended position, particularly on your left side, which allows the best blood flow to your baby and improves kidney function. Lying flat on your back compresses the large vein that returns blood from your lower body to your heart, which can cause dizziness and reduce blood flow to the baby.
If you can’t stay on your left side all night, any side position works. Placing a pillow between your knees and another under your belly creates a slight tilt that takes pressure off your hips. A pillow behind your back can keep you from rolling over. Many women find that a full-body pregnancy pillow simplifies the whole arrangement. If you wake up on your back, don’t panic. Simply roll to your side and reposition. The fact that you woke up likely means your body was already signaling discomfort.
What Happens at Your Prenatal Visit
At 38 weeks, you’re likely seeing your provider weekly. A typical visit includes checking your blood pressure, measuring your belly, and listening to the baby’s heartbeat. Your provider may offer a cervical check to assess dilation and effacement, which is the thinning and softening of your cervix.
Don’t read too much into those numbers. Some women walk around at 2 centimeters dilated and 30% effaced for weeks before labor begins. Others stay at zero until a few days before delivery. Cervical progress is a snapshot, not a prediction. It tells your provider where you are right now but can’t reliably forecast when labor will start.
If you tested positive for Group B strep (a common bacteria carried by about 25% of women), your provider will have noted this in your chart. You’ll receive antibiotics through an IV during labor. Ideally the antibiotics run for at least four hours before delivery, but if labor moves quickly, even a shorter course reduces the risk of passing the bacteria to your baby. This won’t change your labor experience in any meaningful way beyond having an IV line.
Signs That Labor Is Starting
Real labor contractions differ from Braxton Hicks in a few key ways: they come at regular intervals, get progressively closer together, grow stronger over time, and don’t ease up when you change position. A common guideline is to contact your provider or head to the hospital once contractions are coming every five minutes and have maintained that pattern for at least one hour.
Other signs to watch for include your water breaking (a gush or steady trickle of fluid), persistent lower back pain that comes in waves, and a bloody show, which is pink or blood-tinged mucus. Not every woman experiences all of these, and they don’t always happen in a predictable order. Some women have their water break before contractions start, while others don’t until well into active labor.
Tracking Your Baby’s Movement
Fetal movement remains one of the most important things to pay attention to at 38 weeks. Your baby has less room to move now, so the big kicks you felt at 28 weeks may feel more like rolls, pushes, and stretches. The type of movement matters less than the pattern. You should still feel your baby moving regularly throughout the day.
If movement seems to slow down, do a kick count: sit or lie on your side and time how long it takes to feel 10 movements. Kicks, flutters, swishes, and rolls all count. Ten movements within two hours is considered typical. If you don’t reach 10 in that window, or if your baby’s movement pattern changes abruptly, contact your provider. A sudden decrease in movement is worth checking out promptly, even if it turns out to be nothing.
Preparing for the Next Two Weeks
Most first-time mothers deliver around 40 weeks, but labor anytime from now through 42 weeks falls within the normal range. This is a good time to finalize practical details: confirm your hospital bag is packed, make sure your car seat is installed, and review your plan for getting to the hospital or birth center, including backup plans for different times of day.
If you’re feeling impatient, you’re not alone. The last weeks of pregnancy are physically demanding and emotionally exhausting. Focus on what you can control: rest when possible, stay hydrated, eat small meals if heartburn is an issue, and keep moving with gentle walks if your body allows it. Your baby is using these final days to build fat stores, fine-tune brain connections, and prepare lungs for that first breath. It’s a short wait with a significant payoff.