How big is your baby this week? – The first trimester

Throughout your pregnancy, you are no doubt closely monitoring your baby’s development and wondering what your baby’s exact size is.

You can find out just this by taking a look at our fun and informative collection of pictures that will show you how big your baby is, week by week.

Here is the first trimester. Click "next" to view this gallery.

3 to 4 weeks – a sesame seed

Although minute in size, your baby – well, right now an embryo – has formed and is just a group of around 100 cells right now.

5 weeks – an apple seed

Your little baby is still technically an embryo that measures in at a miniscule 0.13 inches.

Although teeny tiny, the little embryo’s heart, brain, spinal cord, muscle, and bones are beginning to develop! How absolutely amazing is that?

6 weeks – a sweet pea

Your little sweet pea has doubled in size and is now the size of – well – a sweet pea.

Measuring 0.25 inches, your baby now resembles a little tadpole and the eyes and limb buds begin to form.

There's a likelihood that during an ultrasound, your doctor may be able to hear his heartbeat.

7 weeks – a blueberry

Measuring 0.51 inches, your baby is now the size of a blueberry and is very busy growing at a tremendous pace.

The heart, lungs, intestines, appendix, brain, spinal cord, nostrils, mouth, and eyes are all growing at the same time, so mummy-to-be will need to start a super-nutritious diet to aid her baby’s rapid growth.

8 weeks – a raspberry

Your baby now weighs around 1.13 grams and measures about 0.63 inches.

Yes, your little darling is still teeny tiny but already performing mighty little feats in yet another big week of growth.

Eyelid folds and ears are forming and those little webbed feet and hands will be used for swimming around your womb.

9 weeks – an olive

Your little one has completed another milestone – he is no longer an embryo, but a foetus. Weighing in at around 1.98 grams and measuring 0.9 inches, his heartbeat is now rapid and strong.

Your baby’s neck is now also more developed and his head is a bit more erect. If you have a scheduled ultrasound, you will be able to see your baby dancing in your womb – but he is still too tiny to be felt.

10 weeks – a prune

Your little one’s vital organs are all formed and are starting to function. She is continuing to grow pretty rapidly weighing approximately 3.96 grams and is now over an inch in length at 1.2 inches!

Can you believe that although she is still very small, your baby is starting to look like a baby now and less like a tadpole? She can even bend her arms and legs at the elbows and knees.

11 weeks – a lime

Measuring at 1.6 inches and weighing probably as much as a little lime at 7 grams, your baby’s feet and hands are not webbed anymore.

Tooth buds and hair follicles are forming, and although genitals are already developing, your doctor still won’t be able to tell the gender of your baby by looking at the ultrasound.

12 weeks – a plum

Weighing 13.8 grams and measuring 2.1 inches, your baby is preparing for yet another rapid growth phase during which organs and tissues will grow quite rapidly.

Your baby is also developing reflexes and flexing her tiny toes and hands. You can also heave a sigh of relief that after the 12th week, the chances of a miscarriage drop significantly.

Get ready for the baby’s arrival by adding your due date.

Calculate your due date

Written by

Minoli Almeida

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