First Trimester

Week 12

Your baby is the size of a Plum

Baby Size

Plum

Length

2.1 in (5.4 cm)

Weight

0.49 oz (14 g)

Trimester

First Trimester

Your Baby at Week 12

Week 12 marks the end of the first trimester for many. Your baby is the size of a plum and can now suck their thumb, swallow, and even hiccup.

Key milestone: The brain is rapidly developing. The baby can make sucking motions and swallow.

Your Symptoms

Nausea usually fades. Energy levels return. The bump may be more visible.

Tip for This Week

Schedule your first-trimester screening and nuchal translucency ultrasound if recommended.

Your Body at Week 12

During the first trimester, your body is working overtime to build the placenta and support rapid embryonic development. Hormones like hCG, estrogen, and progesterone surge, causing many of the symptoms you're experiencing. Your blood volume is already increasing, and your uterus is beginning to expand — even if you can't see it yet.

Your baby at week 12 is the size of a Plum, measuring about 2.1 in (5.4 cm) and weighing roughly 0.49 oz (14 g). The focus is on forming all major organ systems that will sustain your baby through the rest of pregnancy and beyond.

Your Baby's Development This Week

Week 12 marks the end of the first trimester for many. Your baby is the size of a plum and can now suck their thumb, swallow, and even hiccup. The key milestone this week is that the brain is rapidly developing. the baby can make sucking motions and swallow.

The first trimester is a period of incredible transformation. From a single cell to a fully formed fetus in just 12 weeks — your baby's development is happening at an astonishing pace. Each week brings new organs, new abilities, and new reasons to marvel at the process.

This week's voice theme

Almost there — the first chapter is nearly complete.

Imagine hearing this every morning — a voice note from your baby that evolves week by week.

Hear your baby's voice →

Frequently Asked Questions

What is the nuchal translucency scan?

An ultrasound done between 11-14 weeks that measures the fluid at the back of the baby's neck to screen for Down syndrome.

Is it safe to share my pregnancy news at 12 weeks?

Many parents announce after 12 weeks because the risk of miscarriage drops significantly after the first trimester.