25 Weeks Pregnant

At a Glance: Week 25

You're now in the final stretch of the second trimester. At 25 weeks, your baby is roughly the size of a rutabaga — about 34 cm (13.6 inches) from head to heel and weighing approximately 660 grams (1.46 pounds). The biggest milestone this week is rapid surfactant production in the lungs, the substance that will eventually allow your baby's air sacs to expand at birth. Your uterus has reached about the size of a soccer ball and now sits well above your belly button.

Most pregnant people feel a noticeable shift around this point: the early second-trimester comfort is giving way to the more obvious physical demands of carrying a baby. Backaches, heartburn, and shortness of breath often appear or intensify this week.

Your Baby's Development This Week

Week 25 is a period of intense maturation rather than new feature formation. The structures laid down earlier are now refining and beginning to function:

• Lungs: The capillaries that will exchange oxygen are developing, and cells in the alveoli are beginning to produce surfactant. Without enough surfactant, lungs cannot inflate properly — this is the single biggest reason 25 weeks is considered a critical period for viability.
• Brain: The cerebral cortex is layering into the folds we associate with a mature brain. Neural connections are forming at a rate of millions per minute.
• Eyes: Eyelids, fused since the first trimester, will begin to open in the next week or two. Your baby can already perceive light and dark through closed lids.
• Ears: The cochlea and auditory nerves are well developed. Your baby responds to your voice, music, and loud external sounds with measurable heart-rate changes.
• Skin: Skin is still translucent and red but is beginning to thicken. Fine hair (lanugo) covers the body, and a waxy coating called vernix protects the skin from amniotic fluid.
• Muscle and fat: Your baby is gaining about 200 grams per week, much of it as muscle and the beginnings of subcutaneous fat that will smooth out the skin's wrinkled appearance.

Your Body and Symptoms This Week

At 25 weeks, your blood volume has expanded by roughly 40–50%, your heart is pumping harder, and progesterone continues to relax smooth muscle throughout your body. Common symptoms this week include:

• Lower back and pelvic pain from postural changes and ligament relaxation
• Heartburn and indigestion as the uterus presses upward on the stomach
• Constipation and hemorrhoids from slowed digestion and pressure on pelvic veins
• Nighttime leg cramps, especially in the calves
• Mild swelling in the ankles and hands
• Restless legs syndrome — an irresistible urge to move the legs at rest
• Itchy belly as skin stretches
• "Pregnancy brain" — forgetfulness and mild distractibility
• Snoring or nasal congestion caused by pregnancy rhinitis

These are uncomfortable but generally not dangerous. Sharp, persistent pain, regular contractions, bleeding, severe headaches, or sudden swelling — particularly in the face and hands — should be reported to your provider promptly.

Nutrition: What to Eat and Avoid This Week

In the late second trimester, calorie needs increase by about 340 kcal per day above your pre-pregnancy baseline (NIH). More important than calories is the quality of what you eat:

• Iron: Your blood volume expansion is now demanding more iron. Aim for 27 mg/day. Good sources include lean red meat, lentils, spinach, and fortified cereals. Pair plant iron with vitamin C (citrus, peppers) for better absorption.
• Calcium: 1,000 mg/day is recommended throughout pregnancy. Your baby is mineralizing bones rapidly. Sources include dairy, fortified plant milks, sardines, tofu set with calcium, and leafy greens.
• Omega-3 DHA: Crucial for brain and eye development. Aim for 200–300 mg DHA daily from low-mercury fish (salmon, sardines) or an algae-based supplement.
• Protein: About 75–100 g/day supports your baby's rapid muscle and tissue growth.
• Hydration: Aim for 2.3–3 liters of fluid daily; this also helps with constipation and Braxton Hicks.

Avoid: high-mercury fish (shark, swordfish, king mackerel, tilefish), unpasteurized dairy and juices, raw or undercooked meat and eggs, processed deli meats unless heated steaming hot, raw sprouts, and alcohol entirely. Limit caffeine to under 200 mg per day (about one 12-oz coffee), per ACOG guidance.

Movement and Exercise

ACOG recommends at least 150 minutes of moderate-intensity aerobic activity per week throughout uncomplicated pregnancies. At 25 weeks, the safest and most beneficial activities include:

• Brisk walking (still excellent at this stage)
• Swimming and water aerobics — wonderful for relieving back pain
• Stationary cycling
• Prenatal yoga and Pilates (avoid deep twists and supine positions held longer than a few minutes)
• Light strength training, avoiding heavy lifting and breath-holding

Avoid at 25 weeks: contact sports, scuba diving, hot yoga, exercises that involve lying flat on your back for extended periods (the uterus can compress the vena cava), activities with a high fall risk (skiing, horseback riding), and anything that leaves you breathless or causes pelvic pain. Stop and call your provider if you experience contractions, bleeding, fluid leakage, dizziness, or chest pain during exercise.

Mental and Emotional Wellbeing

Around week 25, the reality of becoming a parent often hits more concretely — the baby's movements are unmistakable, the belly is undeniable, and the third trimester is in sight. It's common to feel a mix of excitement, anxiety about birth, and worries about finances, childcare, or relationships. This is normal.

Sleep quality often begins to decline this week: getting comfortable is harder, bathroom trips multiply, and vivid pregnancy dreams are common. Tools that help include sleeping on your left side with a pregnancy pillow, dimming screens after dinner, and using a consistent wind-down routine.

Partner involvement matters: shared prenatal appointments, talking and reading to the baby together, and discussing parenting expectations now reduces conflict later. If you notice persistent sadness, hopelessness, or anxiety that interferes with daily life, screen for prenatal depression and anxiety with your provider — both are common and very treatable.

Common Concerns and When to Call Your Doctor

Call your provider promptly if you experience any of the following at 25 weeks:

• Any vaginal bleeding (light spotting after intercourse can be normal, but report it)
• Leaking or gushing of clear fluid
• Regular contractions (more than 4–6 per hour) before 37 weeks
• Severe or persistent headache, blurred vision, or upper-right abdominal pain — possible signs of preeclampsia
• Sudden swelling of the face or hands
• Burning with urination or flank pain (UTIs are common and can trigger preterm labor)
• A noticeable decrease in fetal movement compared to your baby's pattern
• Fever above 38°C (100.4°F)

Tests and Appointments This Week

At 25 weeks, your prenatal visits are typically every 4 weeks but will soon shift to every 2 weeks. Your provider may schedule the glucose challenge test between weeks 24 and 28 to screen for gestational diabetes. This involves drinking a sugary solution and having blood drawn one hour later. If results are elevated, a longer follow-up test (3-hour GTT) is scheduled.

If you are Rh-negative, you'll discuss Rh immunoglobulin (RhoGAM), typically given at 28 weeks. Your provider may also check iron levels and offer the Tdap vaccine, recommended between weeks 27 and 36 by the CDC.

Tips for Week 25

• Start tracking baby's movement patterns. You don't need formal kick counts yet, but noticing when your baby is most active helps you recognize changes later.
• Invest in a pregnancy pillow. A C- or U-shaped pillow supports your belly and back and significantly improves sleep.
• Begin researching childbirth classes. Most ideal classes are booked weeks 24–32 and run for four to six weeks.
• Tour your delivery hospital or birth center. Knowing the parking, check-in process, and unit layout reduces anxiety on the day.
• Drink water before you feel thirsty. Hydration helps with Braxton Hicks, cramps, constipation, and amniotic fluid volume.

Preparing for What's Next

The third trimester begins at 28 weeks, just three weeks away. Now is the ideal window for several "before-it-gets-harder" tasks: planning the nursery layout, registering for baby essentials, finalizing your maternity leave plan with your employer, choosing a pediatrician (interview at least one), and putting your birth preferences into a working draft. You don't need to make every decision now, but having the structure in place reduces last-minute stress and lets you focus on rest in the final weeks.

Frequently Asked Questions About Week 25