At 21 weeks pregnant you are in the second trimester, with about 19 weeks to go until a 40-week due date. Weeks are counted from the first day of your last period, so this is roughly month 5 of pregnancy.
How big is your baby at 21 weeks?
Around week 21, your baby is often compared to a carrot. Fruit and vegetable comparisons are a friendly way to picture the size, not an exact measurement.
The second trimester covers weeks 14 to 27. Many people find it the more comfortable stretch, and baby movements are often first noticed around this time.
Your body at 21 weeks
Your appetite may be strong. Heartburn and swollen ankles can start, and kicks get more regular.
What is going on
Your baby's growth increases your calorie needs a little, usually about 300 to 350 extra calories a day in the second trimester, not double. Heartburn starts for many as the womb pushes on the stomach.
What can help
Eat smaller meals, avoid lying down right after eating and raise your head with a pillow at night.
Other weeks
19 weeks pregnant · 20 weeks pregnant · 22 weeks pregnant · 23 weeks pregnant
See all weeks on the pregnancy week by week page, or try the interactive week-by-week guide.