18 Weeks Pregnant
Summary
Size
bell pepper
Length
14.2 cm
Weight
190 g
Until due date
22 weeks
18 / 40 week
%45
What's Happening With Your Baby
The ears have settled into their final position and the baby hears outside sounds more clearly. The myelin sheath is beginning to wrap the nerves. In girls the uterus and fallopian tubes have formed; in boys the genitals are now distinct.
What's Changing For You
First movements are felt around now in most first pregnancies. Your belly is obvious and clothes are getting tight.
To Do This Week
Book your detailed anatomy scan for weeks 18 to 23.
Don't lie flat on your back for long; lying on your left side is best for circulation.
Start noting movements as you notice them — it will matter in later weeks.
This Week's Checkup
The detailed anatomy scan is done between weeks 18 and 23, examining organ development one by one.
Frequently Asked Questions
How many months is 18 weeks pregnant?
Week 18 of pregnancy falls in month 5 and in the second trimester. Pregnancy months don't run in neat four-week blocks, so the week-to-month conversion rarely lands on a whole number — which is why pregnancy is tracked in weeks.
How big is the baby at 18 weeks?
At 18 weeks your baby is roughly the size of a bell pepper: around 14.2 cm long and 190 grams. These are averages; clear variation between babies is normal, and what matters is the growth curve your doctor is tracking.
How long is left at 18 weeks pregnant?
Assuming a 40-week pregnancy, you have around 22 weeks left at week 18. Most births happen between weeks 37 and 42, so a due date is a range rather than a fixed day.
What should I watch out for at 18 weeks?
Book your detailed anatomy scan for weeks 18 to 23. Don't lie flat on your back for long; lying on your left side is best for circulation. Start noting movements as you notice them — it will matter in later weeks.
Track your pregnancy week by week
Baby Wallie brings your baby's weekly development, your health logs and AI-powered nutrition, sleep and breathing programs into one app. Free for 7 days.
Related Guides
When To Seek Care Immediately
Whatever week you are in, contact your doctor or the nearest health facility without waiting if you have: vaginal bleeding or fluid loss, severe persistent abdominal pain, a severe headache, blurred vision or flashing lights, sudden swelling of the hands or face, a fever above 38 °C, burning on urination with fever, persistent vomiting, fainting, or — after week 28 — a clear reduction in your baby's movements. In these situations reach real medical care rather than an app or a web search.
This content is for informational purposes only and does not replace medical advice. Always consult your doctor or midwife about your own or your baby's health.