7
Week 7 · First trimester
Twins are the size of grains of rice
Your twins are tiny, 1/166 of an inch to 1 inch.
Weeks 7–40, built for two
Twin pregnancy, week by week
A quick look at how your twins grow each week — their size and a highlight — from week 7 to your due date. Open any week in the free app for the full per-twin guide.
Every week, two babies
Each week below shows what your twins are sized like plus one quick highlight. The full app adds per-twin sizes and weights, "for mom," "your twins," to-dos, and cited sources.
8
Week 8 · First trimester
Twins are the size of blueberries
Your babies are measuring almost an inch now!
9
Week 9 · First trimester
Twins are the size of grapes
Your babies' eyelids are now covering their eyes.
10
Week 10 · First trimester
Twins are the size of kumquats
Each twin is about 1.2 inches long.
11
Week 11 · First trimester
Twins are the size of figs
Each twin is about 1.6 inches long.
12
Week 12 · First trimester
Twins are the size of limes
They are the size of a passion fruit.
13
Week 13 · First trimester
Twins are the size of peapods
Your little embryos are now called fetuses.
14
Week 14 · Second trimester
Twins are the size of lemons
They are 3.2 – 4.1 inches long: about the size of a nectarine.
15
Week 15 · Second trimester
Twins are the size of apples
They are about 4 inches: about the size of an apple.
16
Week 16 · Second trimester
Twins are the size of avocados
They are about 6 inches long.
17
Week 17 · Second trimester
Twins are the size of turnips
Each twin is about the size of a pear, and gaining weight rapidly.
18
Week 18 · Second trimester
Twins are the size of bellpeppers
Your babies are about the size of a bell pepper and have now outgrown the placenta.
19
Week 19 · Second trimester
Twins are the size of tomatoes
Your twins are about the size of a large mango.
20
Week 20 · Second trimester
Twins are the size of bananas
Your babies are the size of an artichoke with stems.
21
Week 21 · Second trimester
Twins are the size of carrots
The twins are the size of carrots.
22
Week 22 · Second trimester
Twins are the size of spaghetti squashes
Your twins are the size of a papaya or spaghetti squash.
23
Week 23 · Second trimester
Twins are the size of mangos
Your babies are the size of large mangoes.
24
Week 24 · Second trimester
Twins are the size of ears of corn
They are the length of an ear of corn.
25
Week 25 · Second trimester
Twins are the size of rutabagas
Your twins are the length of two rutabagas.
26
Week 26 · Second trimester
Twins are the size of scallions
Your babies are the length of two scallions.
27
Week 27 · Second trimester
Twins are the size of cauliflowers
The twins are the length of two heads of cauliflower.
28
Week 28 · Third trimester
Twins are the size of eggplants
Your babies are the length of two large eggplants.
29
Week 29 · Third trimester
Twins are the size of butternut squashes
Your twins are the length of two butternut squashes.
30
Week 30 · Third trimester
Twins are the size of cabbages
Your babies are the length of two large cabbages.
31
Week 31 · Third trimester
Twins are the size of coconuts
Your twins are the length of two coconuts.
32
Week 32 · Third trimester
Twins are the size of jicamas
Your babies are the length of two jicamas.
33
Week 33 · Third trimester
Twins are the size of pineapples
Your twins are the length of two pineapples.
34
Week 34 · Third trimester
Twins are the size of cantaloupes
They are the length of two cantaloupes.
35
Week 35 · Third trimester
Twins are the size of honeydew melons
They are the length of two honeydew melons.
36
Week 36 · Third trimester
Twins are the size of heads of romaine lettuce
They are the length of two heads of romaine lettuce.
37
Week 37 · Third trimester
Twins are the size of swiss chards
They are the length of two swiss chards.
38
Week 38 · Third trimester
Twins are the size of leeks
They are the length of two leeks.
39
Week 39 · Third trimester
Twins are the size of mini watermelons
They are the length of two mini-watermelons.
40
Week 40 · Third trimester
Twins are the size of pumpkins
They are the length of two small pumpkins.