Your baby this week
Third trimester, here you go. Your baby's heart beats about 140 times a minute, much faster than yours. Your baby can blink and spends a lot of time sleeping.
Week 28 begins the third trimester. Your baby sleeps a lot, may be dreaming (rapid eye movement sleep can be seen) and can blink. As fat builds up, the skin smooths out. Visits get more frequent from here, typically every two weeks until 36 weeks and then weekly. It's a good time to plan the months ahead: where you'll give birth, your birth preferences, the hospital bag, a pediatrician for your baby and a car seat. If you're Rh-negative, this is when the anti-D shot is usually given. Keep paying attention to your baby's movement pattern and call right away if it changes.
By the numbers
Week 28 covers days 196 to 202 counted from the first day of your last period, which is 70% of a 40-week pregnancy. About 84 days remain until a 40-week due date. Since last week, an average baby gains about 5.3 oz (150 g). By date of conception, your baby is about 26 weeks old.
Pregnancy is dated from the first day of your last period, so conception happens around week 2. Your due date is 280 days (40 weeks) from that day, and an early ultrasound may adjust it.
Your body
The third trimester is often the most uncomfortable: sleeping, walking quickly and everyday tasks can all get harder. Lean on others for help.
Tests and to-dos this week
Checkups usually move to every two weeks now. If you're Rh negative, you'll likely get an antibody test and an Rh immune globulin shot around this week.
Glucose screening for gestational diabetes · weeks 24–28 · test
Done earlier if you have risk factors.
Tdap (whooping cough) vaccine · weeks 27–36 · vaccine
Recommended during each pregnancy, preferably early in this window.
Rh immune globulin (if you're Rh negative) · weeks 28–28 · test
Given at 28 weeks, and again within 72 hours after birth if the baby is Rh positive.
Coming up: RSV vaccine (September–January) (from week 32). Full prenatal visit schedule
Tips for the third trimester
- From 28 weeks, go to sleep on your side; if you wake on your back, just roll over.
- Pack your hospital bag and agree with your provider on when to head in.
- Call right away, even at night, if your baby moves less or differently.
- Know the signs of labor: regular, strengthening contractions, your water breaking or a bloody show.
Call your provider or labor and delivery right away if you have:
- your baby is moving less or differently than usual
- your water breaks, especially if the fluid is green, brown or smells bad
- bright red bleeding or constant, severe belly pain
- a severe headache, vision changes, pain under the ribs or sudden swelling
- intense itching, especially on the palms and soles
In an emergency, call 911.
Last week and next week
Last week (27): The lungs have come a long way but still need weeks to mature.
Next week (29): Your baby is fully formed and now focused on growing and maturing.
Frequently asked questions
How big is the baby at 28 weeks?
About the size of a butternut squash: about 15 in (38 cm) · 2.6 lb (1,190 g), measured head to heel. These are rounded averages, and every baby grows at their own pace.
How many months is 28 weeks pregnant?
28 weeks is in month 7 and the third trimester. About 12 weeks (84 days) remain until a 40-week due date. Months are approximate; providers count weeks and days.
How often are prenatal visits in the third trimester?
Typically every two weeks from 28 to 36 weeks, then weekly until birth. Your provider may schedule more visits if you have a complication.
What's the next test or appointment after week 28?
Next up: RSV vaccine (September–January), from week 32. Your provider may schedule things differently depending on your health and local practice.
Sources
- WHO Fetal Growth Charts (Kiserud et al., PLoS Med 2017)
- INTERGROWTH-21st crown-rump length standard (Papageorghiou et al., 2014)
- Hadlock et al.: In utero fetal weight standard (Radiology 1991)
- NHS: Week-by-week guide to pregnancy
- NHS: Pregnancy symptoms you need to get help for
- ACOG: How Your Fetus Grows During Pregnancy
- ACOG: Routine Tests During Pregnancy
- ACOG: Prenatal Genetic Screening Tests
- CDC: Vaccine Recommendations Before, During, and After Pregnancy
- Office on Women's Health: Prenatal care and tests
- Hungarian Decree 26/2014 (IV. 8.) EMMI on prenatal care
- NNGYK (Hungary): 2026 vaccination methodology letter
- ACOG – Group B Strep and Pregnancy (Committee Opinion 797)
- ACOG – The Rh Factor
Last reviewed: November 14, 2026 · Kitpebble editorial team
This page is for general information. It isn't medical advice or a diagnosis and doesn't replace your OB-GYN or midwife. Sizes are rounded averages. Our editorial policy