23 Weeks Pregnant
At 23 weeks pregnant your baby is about the size of a large mango — roughly 11.5 inches and around 1 pound 1 ounce — and fat is starting to fill in under the skin. Until now your baby has looked thin and a little translucent; from here on, fat smooths out the wrinkles week by week. Hearing is sharp now, and this week sits right at the start of the viability window.
Your week at a glance
| This week | Details |
|---|---|
| Baby size | About a large mango, roughly 11.5 in and 1 lb 1 oz (about 500 g) |
| What is developing | Subcutaneous fat, sharp hearing, fingerprints, lung airways, fast brain growth |
| Your symptoms | Rib discomfort, shortness of breath, Braxton-Hicks, swollen feet, leg cramps |
| To-do | Mind your posture, ask about the glucose screen at 24–28 weeks, line up classes |
How big is your baby at 23 weeks?
Your baby is about the size of a large mango or a small grapefruit this week — roughly 11.5 inches from head to heel and around 1 pound 1 ounce (about 500 grams). The big new development is that fat is starting to accumulate quickly under the skin. Fat will fill in week by week, smoothing out the wrinkles, plumping up the cheeks, and helping with temperature regulation after birth. The skin is still a bit pink or red because the blood vessels show through, but pigment is steadily increasing. Tiny ridges are forming the unique fingerprints and footprints your baby will keep for life.
Hearing is now quite sharp. Inside the inner ear, the small structures are mature enough that your baby can pick out distinct voices, follow rhythms, and react to changes in volume or tone. Loud sudden noises may make your baby jump; music with a steady beat sometimes settles a baby down. Lung development is moving forward too: the airways are branching, the small blood vessels around them are forming, and special cells are beginning to prepare for surfactant — the substance that lets the tiny air sacs open after birth. The brain is growing fast, with billions of new neurons making connections.
This week sits right at the start of what doctors call the "periviable" window, which generally runs from about 22 to 25 weeks. Babies born at 23 weeks face real risks, but with intensive care in a level III or IV NICU, survival is meaningfully possible — and the odds improve significantly with each additional week. Most pregnancies go on uneventfully well past this point; it is just a milestone worth knowing about. In the meantime, your baby is busy moving — rolling, kicking, stretching, swallowing amniotic fluid, hiccuping, and occasionally giving a strong enough jab that you look down and laugh.
23 weeks pregnant symptoms
Your uterus is rising up under your ribs now, and the bump is making itself known in new ways. Most of what you feel this week is the predictable physics of carrying a growing baby:
- Mild rib discomfort, especially on the right, as your baby kicks upward or the uterus presses on the lower ribcage
- Shortness of breath during everyday exertion — stairs, hurrying, carrying groceries — as the diaphragm has less room
- Braxton-Hicks contractions — a painless tightening across the bump that lasts 30 seconds to a couple of minutes and eases with rest
- A deepening linea nigra, stretch marks, and swollen feet by evening
- Leg cramps at night, vivid dreams, dry skin, and a stuffier nose
- Heavier hair, faster nail growth, and bleeding gums when you brush
- A libido that may be high, low, or all over the place
Braxton-Hicks are not the same as labor: real contractions get stronger, longer, and closer together over time and do not stop with rest. The viability milestone lands differently for different people — some feel reassured, others find it brings unexpected worry. Both are normal; if anxiety is keeping you up, mention it at your next visit.
Taking care of yourself this week
As your bump grows, posture really matters. Avoid slouching when you sit; choose a chair with good lumbar support, keep your feet flat on the floor, and consider a small pillow behind your lower back. If you work at a desk, set your monitor at eye level and get up to walk for a few minutes every 30 to 45 minutes. When standing, balance your weight on both feet, keep your knees soft, and engage your core gently. Side-sleeping with a pillow between your knees and another supporting the bump takes pressure off the hips and low back.
- Skip refrigerated smoked seafood — lox, nova-style salmon, smoked trout, kippered fish — unless fully cooked into a hot dish; canned or shelf-stable versions are safe.
- Heat deli meats, cold cuts, hot dogs, and pâté until steaming hot (165°F), and stick with pasteurized dairy.
- Wash all produce well under running water, including pre-washed greens, and wash melons before cutting into them.
- Choose a soft-cup maternity or sleep bra without rigid underwires; a nursing bra you can also wear postpartum is a nice two-for-one.
- Spread out the prep — register for a childbirth and breastfeeding class, line up infant CPR, and start interviewing pediatricians.
Keep your fridge below 40°F and eat or toss leftovers within three to four days. Cook fish to 145°F, poultry to 165°F, and ground meats to 160°F. Gentle daily movement — walks, prenatal yoga, swimming — continues to help with circulation, mood, and sleep.
Appointments & tests
For most uncomplicated pregnancies, week 23 is a quieter stretch. Prenatal visits are typically about every four weeks through the second trimester. If you have a visit this week, expect the standard rhythm: a check of your blood pressure, weight, and urine; a listen to your baby's heartbeat with a Doppler; a measurement of your fundal height (around 21 to 25 centimeters this week); and a discussion of any new symptoms or questions. Your provider may briefly talk through what to do if you ever notice early signs of preterm labor — regular tightenings, persistent low back pain, pelvic pressure, or leaking fluid.
For pregnancies that are being more closely monitored — a history of preterm birth, a short cervix, twins, gestational hypertension, prior preeclampsia, or growth concerns — surveillance often steps up around now. That can mean more frequent visits, cervical length ultrasounds, growth scans, and sometimes a referral to a maternal-fetal medicine specialist. None of this means something is wrong; it means your team is paying closer attention. If you have been told you are higher-risk, ask exactly what extra monitoring looks like and what symptoms should prompt a call.
The next big appointment on most calendars is the gestational diabetes glucose screen, usually between weeks 24 and 28. Ask your provider when yours is scheduled and whether to fast beforehand (usually you do not for the one-hour test). While you are talking dates, also ask about the Tdap vaccine (recommended every pregnancy between 27 and 36 weeks), the seasonal flu shot, and the RSV vaccine if you are in the right window during RSV season.
Call your provider if
- Regular, painful uterine contractions — especially more than four to six in an hour — that do not ease with rest and water
- New, persistent pelvic pressure that feels like something is bearing down, or a constant low backache that comes in waves
- A sudden gush or steady trickle of clear fluid from the vagina, or any vaginal bleeding beyond very light spotting
- A severe or persistent headache, sudden visual changes, severe upper-belly pain on the right, or sudden swelling of the face and hands
- Fever above 100.4°F, burning with urination, persistent vomiting, intense itching of the palms and soles, or a sustained change in your baby's movement
Reflects Mayo Clinic and Cleveland Clinic second-trimester fetal-development references and Mayo Clinic fundal-height guidance, 2024–2026.
Related questions
- How big is the baby at 23 weeks pregnant?
- About the size of a large mango or a small grapefruit — roughly 11.5 inches from head to heel and around 1 pound 1 ounce (about 500 grams). Fat is starting to fill in under the skin, smoothing out the wrinkles.
- Is a baby viable at 23 weeks?
- Week 23 sits at the start of the periviable window, which runs from about 22 to 25 weeks. Babies born at 23 weeks face real risks, but with intensive care in a level III or IV NICU, survival is meaningfully possible, and the odds improve significantly with each additional week. Most pregnancies continue well past this point.
- Can my baby hear me at 23 weeks?
- Yes. Hearing is quite sharp now. Your baby can pick out distinct voices, follow rhythms, and react to changes in volume or tone. Loud sudden noises may make your baby jump, and music with a steady beat sometimes settles a baby down.
- When is the glucose screening test in pregnancy?
- The gestational diabetes glucose screen is usually done between weeks 24 and 28. Ask your provider when yours is scheduled. For the standard one-hour test you usually do not need to fast — you drink a sweet glucose solution and have your blood drawn an hour later.
Sources & further reading
ParentFlow: one free app, pregnancy to age six
ParentFlow follows your pregnancy week by week — baby size, what's developing, your symptoms, and the appointments and warning signs that matter — then becomes a free baby tracker for feeds, sleep, and growth after birth. Free on iPhone and Android.
App Store Google Play Open Web AppThis article reflects current ACOG, Mayo Clinic, Cleveland Clinic, CDC, and FDA guidance and is for educational purposes only. It does not constitute medical advice. ParentFlow is a wellness companion — not a substitute for your obstetric provider. For any medical concern, contact your healthcare provider.