At 23 weeks pregnant, your baby is roughly the size of a large mango, measuring about 11 inches from head to heel and weighing around one pound. Your belly has grown noticeably past your navel, and you’re likely feeling regular, unmistakable kicks. This is a milestone week: the baby is developing rapidly on the inside, and your body is showing clear signs of the work it’s doing on the outside.
How Big Your Baby Is Now
Crown-to-heel length at 23 weeks is approximately 11 to 11.5 inches, with weight hovering around 500 to 550 grams (just over one pound). That large-mango comparison is helpful for imagining the overall proportions, but the baby is longer and leaner than a mango, with arms and legs that are increasingly proportional to the torso. The head is still relatively large compared to the rest of the body, but less dramatically so than earlier in pregnancy.
What Your Baby Looks Like
The skin at 23 weeks is thin, wrinkled, and somewhat translucent, with a reddish tone from the blood vessels visible underneath. There isn’t much fat stored yet, so the baby looks lean and bony. A fine layer of soft hair called lanugo covers most of the body, helping a waxy, white coating called vernix stick to the skin. That coating protects the skin from the amniotic fluid surrounding it.
Facial features are well-formed by now. The eyelids are fused shut but nearly ready to open, and the lips, eyebrows, and tiny fingernails are all visible. Fingerprints and footprints are forming. If you were to see the baby on a detailed ultrasound, you’d recognize a clearly human face, though still small and delicate.
Key Developments Happening Inside
The lungs are hitting an important milestone this week. They’re beginning to produce surfactant, a substance that allows the tiny air sacs in the lungs to inflate with air and prevents them from collapsing and sticking together when they deflate. The lungs are far from ready to breathe on their own, but surfactant production is the first critical step toward that ability.
The brain is developing rapidly, building the dense network of connections needed for movement, sensory processing, and eventually thought. Your baby can hear sounds now. Loud noises from outside your body, your heartbeat, your voice, and the gurgling of your digestive system all reach the baby through the amniotic fluid. Many babies at this stage will startle in response to a sudden loud sound. They’re also establishing sleep and wake cycles, spending most of their time asleep but moving actively during wakeful periods.
What Your Belly Looks Like
Your uterus now extends about 3 centimeters above your belly button. A general rule of thumb from about 20 weeks onward is that the distance from your pubic bone to the top of the uterus, measured in centimeters, roughly matches your week of pregnancy, plus or minus 2 centimeters. At 23 weeks, that measurement is typically around 21 to 25 centimeters. Your healthcare provider may start tracking this measurement at prenatal visits if they haven’t already.
How your belly actually looks varies widely from person to person. First-time pregnancies often “show” less than subsequent ones because the abdominal muscles haven’t been stretched before. Your height, torso length, and the position of the baby all affect the shape and size of your bump. Some people look unmistakably pregnant at 23 weeks, while others can still conceal it under loose clothing. None of that reflects how well your pregnancy is going.
Common Symptoms at 23 Weeks
Braxton Hicks contractions often start showing up around this time. These feel like a mild tightening across your belly that comes and goes without a regular pattern. They’re more likely in the afternoon or evening, after physical activity, or after sex. They’re not painful in the way labor contractions are, more of a noticeable squeezing sensation. Staying hydrated and emptying your bladder regularly can reduce their frequency.
Leg cramps are another hallmark of this stage, particularly at night. Stretching your calf muscles before bed, staying active during the day, and drinking plenty of fluids all help prevent them. If one strikes, stretching the affected calf or applying heat can ease it quickly. Swelling in the feet and ankles is increasingly common too, as your body retains more fluid and your growing uterus puts pressure on the veins returning blood from your legs.
You may also notice changes in your skin, including a dark line running down the center of your belly (called the linea nigra), darkening of the skin around your nipples, and stretch marks beginning to appear on your belly, breasts, or hips. Some people develop patches of darker skin on the face. These changes are driven by hormones and are completely normal.
Viability: What 23 Weeks Means Medically
Week 23 is considered the earliest edge of viability, the point at which survival outside the womb becomes possible with intensive medical support. According to the American College of Obstetricians and Gynecologists, survival rates for babies born at 23 weeks range from about 23% to 27%, and nearly all survivors face significant health challenges. Before 23 weeks, survival drops to 5 to 6%, with serious complications in virtually every case. These numbers underscore just how much development still needs to happen, but they also explain why reaching 23 weeks is considered a meaningful threshold in high-risk pregnancies.
What’s Coming Up Soon
Between 24 and 28 weeks, you’ll likely be scheduled for a glucose screening test that checks for gestational diabetes. This involves drinking a sugary solution and having your blood drawn about an hour later. If your results come back elevated, a longer follow-up test confirms the diagnosis. It’s one of the most routine prenatal screenings, and most people pass without any issues. If you haven’t been told about it yet, expect to hear about scheduling it at your next appointment.