Second trimester: weeks 13 to 28

The second trimester is the middle three months of your pregnancy. This is a time when lots of women tell the world they’re pregnant and begin to feel like the pregnancy is more ‘real’.

The second trimester of your pregnancy is from week 13 to week 28 – roughly months four, five and six.

As well as feeling and looking more pregnant during these weeks, you may also have more energy than you did in the first trimester. This will come as a great relief if you have been struggling with sickness, tiredness or anxiety about getting through the  first trimester.

13 weeks pregnant – all you need to know

Welcome to the second trimester of pregnancy, a trimester of growth where your bump will get bigger and you’ll start to feel your baby moving.

What does my baby look like in week 13?

Your baby is growing fast – and you may be too! You might hear their heartbeat for the first time at your antenatal appointments.

Your baby now weighs around 25g.

Although you won’t be feeling baby move just yet, they’re dancing around inside you. As time goes on their jerky motions are turning into slower, more purposeful ones.

Your baby’s hands find their way to their mouth and sometimes they look like they might be yawning or breathing. At this stage your baby only sleeps for a few minutes at a time but later in pregnancy, they’ll start sleeping for longer stretches and you might even notice a pattern, or routine emerging.

Your baby’s ovaries or testes have developed inside their body and a tiny willy or penis is now forming where a bump was before.

14 weeks pregnant – all you need to know

Your growing baby is now around the size of a kiwi fruit, measuring about 85mm from the top of their head to the bottom.

What does my baby look like in week 14?

Your baby has started swallowing tiny sips of amniotic fluid. This goes into their stomach, through their kidneys and comes back out as urine.

Your midwife might be able to hear your baby’s heartbeat from 14 weeks. This is done with a hand-held fetal heart rate monitor (known as a hand-held doppler), which is placed on your tummy.

Hearing your baby’s heartbeat for the first time can be a very special moment in a pregnancy and may make your baby feel more real for you. It’s likely you’ll get to have a listen at your 16 weeks midwife appointment.

15 weeks pregnant – all you need to know

Your baby is about the size of a small pear.

What does my baby look like in week 15?

Their hearing is developing and from around now they might be able to hear your voice, the comforting sound of your heartbeat and muffled sounds from the outside world.  

They might also start to sense bright light outside your tummy.

Your baby is covered in fine hair, called lanugo. This will usually disappear some time before they are born, unless they arrive early.

This week your baby might start to get hiccups every now and again. Later in your pregnancy, you’ll probably be able to feel little rhythmic flutters when your baby gets them.

16 weeks pregnant – all you need to know

Your baby is now about the size of a lemon.

What does my baby look like at week 16?

Did you feel a little flutter? Perhaps a bubbling sensation? This could be your baby moving! Don’t worry if you haven’t felt anything like this yet though – it’s still early days.

Your baby’s nervous system continues to develop, and the muscles in their tiny limbs can flex. They can make a fist and might even grab and pull their umbilical cord.

If it’s your second pregnancy you might feel them sooner.

If you could see their face, you might be able to see them making facial expressions, like a frown or squint. They can’t control these facial muscles yet though.

17 weeks pregnant – all you need to know

Your baby is about the size of an orange, about 12cm long, and weighs roughly 150g. Your bump is getting bigger.

What does my baby look like in week 17?

If you could see your baby’s face, you’d notice eyelashes and eyebrows starting to grow.

And if you could take their hand, you’d see they already have a unique fingerprint.

Before this point, your baby’s head was bigger in proportion to their body. Now, however, their body is starting to fill out, and their proportions are starting to even out. 

Your baby’s eyes can move, although their eyelids are still shut, and won’t open again until week 26. The bone tissue in their feet begins to harden.

The placenta continues to grow to keep up with your baby’s needs. By the time you give birth it will weigh about 500g.

18 weeks pregnant – all you need to know

Your baby measures about 14cm this week – roughly the same as a bell pepper!

What does my baby look like in week 18?

When your baby is born, you may hear about using white noise to help them sleep. The reason this is such a great trick is because they’re used to noise – the womb is far from silent. At 18 weeks they can hear sounds all around them and might even respond to music or a loud noise.

19 weeks pregnant – all you need to know

Your baby is now around the length of a banana and you may be starting to feel them move. You might even start to feel them actually prodding or kicking you!

What does my baby look like in week 19?

Your baby is growing fast and gaining weight, but doesn’t have much fat on their body yet. They look a bit wrinkled at the moment and won’t start to fill out until the final few weeks of your pregnancy.

Even though your baby probably won’t get their first tooth until they’re about six months old, they are already forming their second teeth, behind the first ones.

20 weeks pregnant – all you need to know

If they stood up straight your baby would be around 26cm tall, nearly the length of an A4 piece of paper!

What does my baby look like in week 20?

Your baby’s skin is now coated in a white, creamy substance called vernix. This is thought to protect their skin while they’re in the womb.

When you see your baby at the anomaly scan, you might see them sucking their thumb. They’re practising their sucking reflex, which is important for when they starts to nurse.

21 weeks pregnant – all you need to know

Wow – you’re halfway there! Your baby is growing hair and starting to look much more like the baby you’ll meet at the end of your pregnancy.

What does my baby look like in week 21?

Your baby weighs in at around 350g and is about as long as a carrot. Although your baby’s ears began to form early on, they’ll start to be able to hear around now. They’ll be able to make out sounds from outside, including your voice and the voices of people around you.

Talk and sing to your bump if you feel like it, and encourage other family members to do the same – it can be a nice way to let others get involved.

It sounds a little strange but your baby has been growing a fine hair called lanugo all over their tiny body over the last few weeks. You’ll be relieved to hear it usually disappears before they’re born.

The hair on their head and eyebrows is starting to become a little thicker at the roots and showing signs of pigment.

22 weeks pregnant – all you need to know

Your baby now weighs around one pound. From around now, they start to weigh more than the placenta. They’re about the size of a bag of sugar.

What does my baby look like in week 22?

Over the next few weeks, your baby’s taste buds will continue to develop and they’ll be busy practising swallowing in readiness for life outside your womb.

What you eat now could affect the flavours your baby prefers after they’re born, so eat plenty of healthy food.

Your baby’s lungs are not yet ready for life outside the womb but they’re developing fast. Even though they can’t breathe in the womb, your baby’s practising breathing movements for life outside.

They get all their oxygen from your blood via the placenta until they take their first breath after they’re born.

Smoking decreases the amount of oxygen in the placenta, so it’s very important to stop if you’re still smoking. It’s not too late, every day without smoke will help your baby’s health.

23 weeks pregnant – all you need to know

Your baby is about 30cm now and roughly the size of a large mango.

They might get hiccups and you may feel the tiny jerks when it happens! They can also suck their thumb.

Have you been feeling flutters and bubbles from your little one? These have probably turned into kicking and little jabs by now. Over the next few weeks they’ll become more noticeable and regular as your baby grows and gets stronger, rolling and dancing inside you.

You might even notice a kind of pattern emerging. Often when you rest, your baby will spring into action and when you’re busy on your feet your baby will be rocked to sleep by the motion.

24 weeks pregnant – all you need to know

Your baby is now about the size of a corn on the cob.

What does my baby look like?

Have you noticed they are getting into a pattern of sleeping and waking? When you’re in bed at night, feeling relaxed and trying to sleep, you might find they’re wide awake and wriggling.

Your baby is now said to be ‘viable’. This means that there is a chance that they would survive if they were born now, even though it is still very early.

A baby born at this stage would need a lot of help in the neonatal unit, as their body is still very immature and not ready to cope in the outside world yet.

25 weeks pregnant – all you need to know

Your baby can respond to light, touch and sound now. You might even notice them jumping or kicking in response to a loud noise.

What does my baby look like in week 25?

Your baby is weeing frequently, and this urine passes into the amniotic fluid. Their brain, digestive system and lungs are developed but they’re not what they call ‘mature’ yet – they will continue to develop as your pregnancy progresses.

26 weeks pregnant – all you need to know

If you could see your baby, you might notice their eyelids open. They’ll soon be blinking.

What does my baby look like in week 26?

Their eye colour at this stage is very likely to be blue. Sometime after they’re born, your baby’s eyes will become the colour they will stay.

Your baby is around 35cm long from the top of their head to their heels, which is nearly the length of your forearm – though they’re is curled up in the womb. They’re about the length of a courgette now.

Your uterus is still pretty roomy and you’ve probably been feeling baby move around vigorously.

Over the next couple of months your baby will be putting on more fat and muscle, and start to look a little less wrinkly and skinny and more like a little cherub.

27 weeks pregnant – all you need to know

Your baby’s about the size of a cauliflower now.

What does my baby look like?

You’re coming to the end of the second trimester now, and your family might find it easier to  •feel your baby’s movements.

If your baby was able to stretch out fully, they could be as much as 37cm long. They’re a tangle of limbs, taking up lots of the space in your womb.

Your baby’s heart rate has slowed down a little, to about 140 beats per minute – although this is still super-speedy compared to your own.

Their heartbeat can now be heard through a stethoscope and your partner might even be able to hear it if they put their ear to your bump – although it can be tricky to find the right spot.

28 weeks pregnant – all you need to know

Your baby weighs about 1kg now and is roughly the size of an aubergine.

What does my baby look like in week 28?

Your baby weighs about 1kg now and is roughly the size of an aubergine. They’re starting to take up more space in your womb and, as the weeks go by, you may start to feel a bit more uncomfortable and tired.

Your baby will be having periods of sleep and periods of activity, which you’ll probably be aware of because of their movements. You may have noticed that these movements are settling into a regular pattern.