expecting you

Baby Size by Week

Published on July 14, 2025

TL;DR: Your baby grows from a poppy seed to a watermelon between weeks 4 and 40. This guide shows what size they are each week using fruit and simple comparisons.

Every week of pregnancy, your baby gets a little bigger — and a lot more real.
It helps to picture their growth using something familiar.

Here’s a week-by-week guide to baby size using fruit (and a few veggies and snacks too).

First Trimester

Week 4: Poppy seed
Week 5: Sesame seed
Week 6: Lentil
Week 7: Blueberry
Week 8: Raspberry
Week 9: Grape
Week 10: Kumquat
Week 11: Fig
Week 12: Lime
Week 13: Peapod

Second Trimester

Week 14: Lemon
Week 15: Apple
Week 16: Avocado
Week 17: Turnip
Week 18: Bell pepper
Week 19: Heirloom tomato
Week 20: Banana
Week 21: Carrot
Week 22: Spaghetti squash
Week 23: Mango
Week 24: Ear of corn
Week 25: Rutabaga
Week 26: Scallion

Third Trimester

Week 27: Cauliflower
Week 28: Eggplant
Week 29: Butternut squash
Week 30: Cabbage
Week 31: Coconut
Week 32: Jicama
Week 33: Pineapple
Week 34: Cantaloupe
Week 35: Honeydew melon
Week 36: Romaine lettuce head
Week 37: Swiss chard bunch
Week 38: Leek bundle
Week 39: Mini watermelon
Week 40: Full watermelon

Your baby doesn’t follow a perfect chart — every pregnancy is different. But these little size snapshots can help you imagine what’s happening each week.

You’re growing a whole human. One fruit-sized stage at a time.