At six months pregnant, you’re in the home stretch of your second trimester, covering roughly weeks 23 through 27. This is when your baby’s development accelerates dramatically, your body adjusts to a noticeably larger uterus, and your prenatal care ramps up with some important screenings. Here’s what’s happening and what you’ll likely experience.
How Big Your Baby Is Now
By the end of month six (around 27 weeks), your baby weighs about 2¼ pounds and measures roughly 13¾ inches from head to heel. That’s a significant jump from the start of the month, when your baby was closer to a pound. This rapid weight gain continues through the third trimester, but right now your baby is transitioning from looking lean and translucent to filling out with fat stores under the skin.
What Your Baby Can Do
The sixth month brings some remarkable developmental leaps. Around week 23, your baby’s lungs begin producing surfactant, a substance that allows the tiny air sacs to inflate and keeps them from collapsing. The lungs are far from ready to breathe air, but this is the critical first step toward functioning outside the womb.
By week 25, your baby can hear and may start moving in response to familiar sounds, including your voice. This is a great time to talk, read aloud, or play music if you want to, though it’s not required for healthy development. Around week 26, your baby’s eyes are fully formed, and the eyelids will open within the next couple of weeks. Your baby is also developing regular sleep and wake cycles, which you’ll probably notice as predictable stretches of activity and quiet.
Why Viability Matters This Month
Week 24 is widely considered the threshold of viability, the point at which a baby born prematurely has a realistic chance of surviving with intensive medical care. Survival rates for infants born at 24 weeks fall between 60 and 70 percent. Those odds improve dramatically with each additional week in the womb. A baby who stays put just two or three weeks longer has a significantly lower risk of both death and long-term health complications. This is one reason your care team pays close attention to any signs of preterm labor from this point forward.
Common Physical Changes
Your uterus now extends well above your belly button, and the physical effects of carrying that extra weight become harder to ignore. Back pain is one of the most common complaints at six months. Your center of gravity has shifted forward, and the hormones that loosen your joints and ligaments for delivery also make your lower back less stable.
Swelling in your feet, ankles, and hands is normal during this stretch. Your body is retaining more fluid, your blood vessels are more permeable, and the growing uterus puts pressure on the veins returning blood from your legs. Mild, symmetrical swelling that worsens at the end of the day is typical. Sudden or severe swelling, especially in your face, is not, and warrants a call to your provider.
Leg cramps, particularly at night, are another hallmark of month six. Staying hydrated, stretching your calves before bed, and keeping up your intake of magnesium-rich foods (nuts, leafy greens, whole grains) can help. You may also notice more frequent heartburn as your uterus pushes your stomach upward, and some breathlessness as it crowds your diaphragm.
Feeling Your Baby Move
If you’ve been feeling flutters and kicks for a few weeks, you’ll notice them getting stronger and more organized this month. By the end of month six, movements shift from occasional taps to rolls, jabs, and visible bumps across your belly. Partners and family members can often feel them from the outside now.
Formal kick counting becomes most important in the third trimester (starting around week 28), but it’s worth getting familiar with your baby’s patterns now. The general guideline is 10 movements, including kicks, rolls, and flutters, within two hours. Most babies hit that number in well under an hour. What matters most is learning your baby’s normal rhythm so you can recognize any significant change later on.
Sleep Gets Harder
Sleeping comfortably at six months pregnant takes some problem-solving. Many providers recommend sleeping on your side, particularly the left side, because lying flat on your back allows the weight of your uterus to compress major blood vessels: the aorta carrying blood to your lower body and the vein returning blood to your heart. This compression can reduce blood flow to both you and your baby.
In practice, you don’t need to panic if you wake up on your back. The concern is about spending long stretches in that position. A pillow between your knees, another behind your back, or a full-length pregnancy pillow can help you stay on your side and support your belly. Some people also find that elevating their upper body slightly reduces heartburn and breathlessness enough to sleep longer stretches.
Screenings You’ll Have This Month
Glucose Challenge Test
Between weeks 24 and 28, you’ll be screened for gestational diabetes. The test involves drinking a sugary solution and having your blood drawn one hour later. A blood sugar reading below 140 mg/dL is considered normal. A result between 140 and 190 mg/dL means you’ll need a longer, three-hour follow-up test to confirm or rule out gestational diabetes. A result of 190 mg/dL or higher typically leads to a diagnosis without further testing. Some clinics use a slightly lower cutoff of 130 mg/dL, so your provider may flag results that seem borderline.
Gestational diabetes is manageable and common, affecting roughly 6 to 9 percent of pregnancies. If you’re diagnosed, you’ll work with your care team on dietary changes and blood sugar monitoring. Some people also need medication. The condition usually resolves after delivery.
Rh Factor Screening
If your blood type is Rh-negative, you’ll have an antibody screening between weeks 24 and 28. This checks whether your body has developed antibodies against your baby’s blood cells, which can happen if your baby is Rh-positive. If no antibodies are found, you’ll receive an injection of Rh immunoglobulin to prevent your immune system from reacting to any fetal blood cells that may cross into your circulation. This is routine and straightforward.
Braxton Hicks vs. Preterm Labor
Many people start noticing Braxton Hicks contractions around month six. These practice contractions are your uterus tightening briefly, usually lasting less than a minute, and happening only once or twice an hour at most. They’re irregular and often stop when you change position: if you’ve been walking, sit down; if you’ve been resting, get up and move.
Preterm labor feels different. Real contractions become regular, longer, and progressively more painful. They typically start at the top of your uterus and radiate down toward your pubic bone, with pain in your lower back and pelvis. Contact your provider if you experience contractions more than four times an hour, persistent lower back pain, pelvic pressure that feels like the baby is pushing down, period-like cramping, or any fluid or blood from your vagina. Changes in your baby’s movement patterns, particularly a noticeable decrease, also warrant a call.
What Else Changes This Month
Your appointments may shift from once every four weeks to every two or three weeks as you approach the third trimester. Your provider will continue monitoring your blood pressure, weight gain, and the size of your uterus at each visit. You may also discuss your birth plan preferences, cord blood banking, and pediatrician selection, though there’s no rush on any of these.
Emotionally, month six is a mixed bag for many people. The novelty of pregnancy may have worn off, physical discomfort is increasing, and the reality of labor and parenthood feels closer. It’s also a period of nesting instinct for some, with a sudden urge to organize, prepare the nursery, or stock up on supplies. Both reactions are completely normal, and so is swinging between the two in the same afternoon.