At 23 weeks pregnant, you’re deep into the second trimester with your baby growing rapidly and your body adapting in noticeable ways. This is a week of significant milestones: your baby’s movements are getting stronger, your belly is visibly expanding, and a key screening test for gestational diabetes is likely just around the corner. Here’s what’s happening this week, from head to toe, for both you and your baby.
How Your Baby Is Developing
Your baby is putting on weight quickly now. At 23 weeks, most babies measure roughly 28 to 30 centimeters (about 11 inches) from crown to heel and weigh around 500 grams, or just over a pound. The skin is still thin and somewhat translucent, but fat deposits are starting to fill things out.
Your baby’s lungs are developing rapidly this week, producing a substance called surfactant that will eventually help the air sacs inflate after birth. The ears are also more developed now, meaning your baby can hear your voice, your heartbeat, and muffled sounds from the outside world. Some parents notice their baby startling or kicking in response to a loud noise.
Fetal Movement at 23 Weeks
If you’ve been feeling flutters, swishing, or rolling sensations over the past few weeks, those movements are becoming more distinct around now. You may start to feel actual kicks, jabs, and elbows rather than the vague “butterflies” of earlier weeks. Some of these movements can catch you off guard, especially when you’re sitting still or lying down at night.
Between 24 and 28 weeks, you’ll start to recognize a pattern to your baby’s activity. Formal kick counting on a chart is no longer widely recommended, but it is important to take time each day to notice your baby moving. You’re building a mental baseline for what’s normal for your baby, which matters more than hitting a specific number. If you notice a clear and sustained drop in movement later on, that’s worth a call to your provider.
Common Symptoms This Week
Your body is working hard to support a growing baby, and at 23 weeks that effort shows up in a handful of predictable ways.
Swollen hands and feet. Mild swelling, especially in your fingers and ankles, is common in the second half of pregnancy. Extra blood volume and fluid retention are the main causes. Elevating your feet when you can and staying hydrated both help. Sudden or severe swelling, particularly in your face, is a different story and warrants a call to your provider.
Braxton Hicks contractions. You may start to notice a mild tightness across your belly that comes and goes. These “practice” contractions tend to show up in the afternoon or evening, after physical activity, or after sex. They’re irregular, don’t get progressively stronger, and usually stop when you change position or rest.
Linea nigra. A dark vertical line running down the center of your belly is a harmless pigmentation change driven by pregnancy hormones. It typically fades on its own after delivery.
Back pain. As your center of gravity shifts forward, the muscles and ligaments in your lower back take on extra strain. This is one of the most common complaints in the second half of pregnancy, and it tends to intensify as the weeks go on.
Managing Back Pain
Back pain at this stage responds well to a combination of posture adjustments, gentle stretching, and the right footwear. When standing, keep your shoulders back and relaxed, your knees slightly bent, and your feet in a comfortably wide stance. If you’re on your feet for long stretches, resting one foot on a low step stool takes pressure off your lower back.
A simple stretch that many people find helpful: get on your hands and knees with your head in line with your back. Pull in your stomach to round your back slightly, hold for a few seconds, then relax back to a flat position. Gradually work up to 10 repetitions. Prenatal yoga classes build on this kind of movement and add core and pelvic floor support.
For sitting, a small pillow or lumbar cushion behind your lower back makes a noticeable difference, especially if you work at a desk. Footwear matters too. Low-heeled shoes with good arch support (think walking shoes or athletic sneakers) are the best choice. High heels shift your balance further forward, and completely flat shoes offer no support.
Gestational Diabetes Screening
If you haven’t already been screened, your glucose challenge test is likely coming up in the next one to five weeks. The standard window is between 24 and 28 weeks, though people at higher risk may be tested earlier. This is one of the routine screenings of the second trimester, and it’s straightforward.
You don’t need to fast or prepare in any special way. You’ll drink a sweet glucose solution, then have your blood drawn about an hour later to see how your body processes the sugar. If the results come back elevated, a longer follow-up test (the glucose tolerance test) confirms whether gestational diabetes is present. Most people pass the initial screen without any issue.
Iron Needs in the Second Trimester
Your blood volume has expanded significantly by now, and your body needs more iron to keep up with red blood cell production. The recommended daily intake during pregnancy is 27 milligrams, but the typical diet only provides about 15 milligrams. That gap is why most prenatal vitamins include iron and why your provider may check your iron levels around this time.
If you’re feeling unusually fatigued, dizzy, or short of breath beyond what feels normal for pregnancy, low iron could be a factor. Eating iron-rich foods like red meat, lentils, spinach, and fortified cereals helps, and pairing them with something high in vitamin C (like citrus or bell peppers) improves absorption.
Viability at 23 Weeks
Twenty-three weeks falls within what doctors call the periviable period, roughly 20 to 26 weeks. This is the earliest window in which survival outside the womb becomes possible with intensive medical intervention. At 23 weeks specifically, survival rates for babies who receive active treatment range from about 23% to 27%, according to the American College of Obstetricians and Gynecologists. Babies born this early face a high likelihood of significant medical complications and long-term health challenges.
This isn’t something most pregnant people need to worry about, but understanding the milestone can be reassuring. Every additional week your baby stays in the womb dramatically improves outcomes.
Signs of Preterm Labor
Preterm labor is defined as labor occurring between 20 and 36 weeks, so it’s worth knowing the warning signs even though the risk at any given week is low. The key symptoms to watch for include:
- Contractions every 10 minutes or more often
- A change in vaginal discharge, including leaking fluid or bleeding
- Pressure in your pelvic area
- A low, dull backache that doesn’t go away with position changes
- Cramps that feel like menstrual cramps, with or without diarrhea
The threshold that warrants immediate attention is six or more contractions in one hour, or any fluid or blood leaking from the vagina. Braxton Hicks contractions are irregular and stop on their own. Preterm labor contractions come at regular intervals and get closer together. If you’re unsure which you’re experiencing, calling your provider is always the right move.