28 weeks pregnant: symptoms and baby development
They open their eyes, and blink.
Third trimesterMonth 75 min read
By Solesia, from public clinical guidanceUpdated
The last stretch begins here. Twelve weeks remain, give or take, and the pregnancy changes pace: your baby, who has spent months building, now spends the weeks putting on weight, and you can feel the difference in how you carry them. Heartburn and an aching back tend to arrive together as the bump grows, ankles can be puffy by evening in warm weather, and the easy middle gives way to something fuller and slower. Inside, the eyes that opened a fortnight ago are learning to focus, and the kicks have a new weight behind them. It is a busier season than the one before, and in a good way.
How big is your baby at 28 weeks
About the size of an eggplant
14.8 in long·2.7 lb
Baby development at 28 weeks
At 28 weeks your baby measures about 14.8 inches from head to heel and weighs around 2.7 pounds, roughly an eggplant. Their eyelids, sealed shut since the first trimester, part this week, and they can open and close their eyes and blink. There is little to see in there, but they turn toward a bright light held against your bump.
Their heartbeat is slowing as the heart grows stronger, to about 140 beats a minute, and it is loud enough now to hear through an ordinary stethoscope. By birth it settles closer to 130. Fat is building under their skin, which is starting to lose its wrinkled, see-through look and take on the smoother, rounder shape of a newborn.
The lungs are maturing, with the branching airways in place and the substance that keeps the air sacs open continuing to build. The brain is folding into its grooves and ridges, and they are settling into cycles of rest and activity that you can often feel: long quiet spells, then a burst of kicks.
Your body at 28 weeks
Your uterus now sits well above your belly button, and the extra weight in front pulls on your lower back. The hormones that loosen your joints for birth loosen your spine too, so backache is expected from here. Flat shoes, sitting with your back supported, and a pillow between your knees at night all help. Heartburn often keeps it company, because the same relaxed muscle that lets your joints move lets stomach acid up; small meals, and nothing in the three hours before bed, take the edge off.
Swelling in your feet and ankles that builds during the day and settles overnight is expected, and heat makes it worse. Sit with your feet up when you can, drink plenty of water, and keep walking: moving your calves pumps fluid back up. Puffy fingers may mean rings come off for a while.
From this week the advice is to fall asleep on your side. The uterus is heavy enough now that lying flat on your back can press on the vessel that returns blood to your heart. Left or right is fine, and if you wake up on your back, just turn over. A pillow behind you helps you stay put.
Common pregnancy symptoms at 28 weeks
- Heartburn. A relaxed valve and a crowded stomach. Small meals, sit upright after eating, and ask about an antacid.
- Backache. Loosened joints and weight in front. Flat shoes, and a hand on your back when you stand up from sitting.
- Swollen ankles and feet. Fluid settling by evening, worse in heat. Feet up, water, and a short walk.
- Trouble sleeping. A bigger bump and a busier mind. Side lying with a pillow under the bump and one between your knees.
- Stretch marks. Skin stretching faster than it can keep up. Moisturizer eases the itch; the marks fade after birth.
- Leg cramps at night. Common in the calf. Straighten the leg, flex your foot, and it lets go.
- Bleeding gums. More blood flow to the gums. A soft brush, and keep flossing; a dental check is fine now.
When to call your provider at 28 weeks
Sudden swelling of your face or hands, especially with a headache or vision changes, is a same-day call. It is the quickest blood-pressure check there is.
Two things are worth a same-day call at any point in pregnancy: bleeding that is more than spotting, and pain that is severe or does not ease. From the second trimester, add fluid leaking and any change in your baby’s usual pattern of movement. You do not need to be sure something is wrong to call; that is what the number is for.
What to do at 28 weeks
- The 28-week visit. A bigger visit than usual: blood pressure, urine, a measure of your bump, and a blood draw that checks for anemia. From here visits are every two weeks.
- RhoGAM if you are Rh-negative. If your blood type is Rh-negative, you get a shot around this week that stops your body reacting to your baby’s blood. A second dose follows after birth if needed.
- Tdap and glucose screening. The whooping cough shot is given between 27 and 36 weeks, and many providers give it now. If your glucose screening has not happened yet, this week is the last of its window.
- Sleep on your side. Starting this week, go to sleep on your left or right side rather than flat on your back. It is about how you fall asleep, not how you wake.
Common questions at 28 weeks
What happens at the 28-week appointment?
The usual checks, plus blood work. Your provider measures your bump, takes your blood pressure and tests your urine, and draws blood to check for anemia and, if you are Rh-negative, to see whether you need a RhoGAM shot. Many also give the Tdap vaccine at this visit. Bring your questions; there is more time than usual.
Is 28 weeks the third trimester?
Yes. The third trimester runs from week 28 to birth, so this is its first week, and you are about seven months along. Twelve weeks remain to your due date, though anywhere from 37 weeks on counts as term, so the real range is closer to nine to fourteen.
Why do I need to sleep on my side from 28 weeks?
By now the uterus is heavy enough that lying flat on your back can press on the large vein that carries blood back to your heart, which reduces the flow to the placenta. Falling asleep on either side keeps it clear. If you wake up on your back, do not worry; just turn over.
How often should I feel my baby move at 28 weeks?
There is no number. By now you know when your baby is usually busy and when they rest, and that pattern should hold steady from here to birth. If it changes, or they seem quieter than usual, call your provider that day rather than waiting to see.
Written from public clinical guidance, including NHS: Week 28, ACOG: How your baby grows, ACOG: Changes in your body, ACOG: The Tdap vaccine and pregnancy, ACOG: Gestational diabetes, NHS: Your baby’s movements, NHS: Swelling in pregnancy and NHS: Back pain. This page is general information, not medical advice, and does not replace your provider.