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Your baby at 17 weeks
You could still hold your baby in the palm of your hand now but he’s getting plumper by the day and his body is starting to fill out to be more in proportion with his head. The placenta is nearly as big as he is this week and it’s working hard to give him all the nutrients he needs.
This is also a very ‘productive’ week, during which he’s creating all manner of bizarre coatings, excretions and emollients. Here are some of this week’s ‘highlights’, if you can call them that…
He’s putting down layers of fat and starting to fill out his wrinkly skin, which has looked a bit too big for his body until now.
This week he also forms a special kind of fat – rather attractively called 'brown fat' – that will insulate him when he's born. It's found at the back of his neck and around his kidneys to protect them.
The downside to floating in an amniotic fluid bath for nine months is gaining the distinctive look of prune. To combat this, your baby develops some protection in the form of a cheesy, white cream that covers his whole body and head, called vernix. It's made from the baby's sebaceous glands (the ones that make oily fluid to protect our skin) and acts as a waterproof layer to protect his delicate skin from becoming chapped by the amniotic fluid. It makes it easier for your baby to get through the birth canal but does make him slippery when he comes out, so the midwives will give him a quick rub down with a towel to remove it. You'll probably see a few remnants of it on your baby's skin straight after birth, though.
The nerves that link his muscles to his brain now have a sophisticated new addition – a special coating called myelin, which speeds up how quickly nerves and muscles are able to communicate with each other. His nerves can send electrical impulses to his muscles fast enough for him to complete quite intricate movements now. He’s not up to figure skating yet, but it’s a definite step forward.
And at 17 weeks he is making lots more meconium (his first bowel movement), which consists of bile salts and acids made in the liver and skin cells he has swallowed from the amniotic fluid. As if the cheesy coating and brown fat weren’t already enough of a treat!
To counter all the gunge this week, he’s doing some pretty clever and cute stuff, too. Inside his brain, the nerve cells are connecting to each other more and more quickly. His eyes are still shut but he can roll them from side to side and his retina can now react to light. He can also hear more and may react to sound, too, if you play loud music.
His heart is beating twice as fast as yours does and is being regulated by the brain already.
If your baby is a girl, she already has a uterus and fallopian tubes by this week.
The bones in his feet are starting to harden.
He’s pretty energetic in there, too, doing somersaults and kicking more forcefully. He will move away from any pressure on your abdominal wall now and an ultrasound probe can make him jump – a hilarious sight if you actually get to see it on the screen.
What size is the baby at 17 weeks?
He is now about 13cm from his crown to his rump, that’s roughly the size of a turnip and weighs about 140g.
Your 17-week bump
Bump size varies enormously but many women find they're starting to get something that is very much more bump than bulge by this stage. You might notice the change in your bump when you're doing things like driving the car and find your seatbelt sits slightly differently to normal. You want to get the lap part of the belt under your bump, by the way, and the diagonal part on your shoulder and between your boobs.
How is your body changing at 17 weeks pregnant?
The textbooks will all promise you’ll feel more energetic now, though some women just feel heavy and cumbersome. However, the majority of women feel less sick and tired and quite enjoy this time in the middle of the second trimester. Some even gad off for a final, child-free holiday – get them!
Your heart is pumping more blood, even faster, around your body and, to avoid your blood pressure going up, your pregnant body adapts by making your blood vessels more elastic. They can then expand to take the extra blood.
You may be more aware of your heartbeat and you can feel occasional missed beats, which is normal. But if you feel that your heart is beating irregularly you should see your doctor and get checked over.
Increased blood flow and an increase in melanin means you may notice some changes to your skin tone. You might see a dark line appear down your bump – the linea nigra – which is caused by pigmentation pooling in the area of your stomach where muscles are stretching. You may also get dark patches appearing on your hands, feet and face, known as chloasma. They all disappear again after pregnancy, so don't worry about them.
And every cloud has a silver lining – just as your waistline finally vanishes, you often find your libido returns. Pregnancy hormones can increase libido but the effect of this is often masked by suffering from pregnancy sickness and tiredness in the first trimester. Lots of women also find they just feel more confident in the buff when they have a definable ‘bump’ (as opposed to a bit of an amorphous blob around the middle).
When does a baby start kicking?
You may start feeling your baby move around this time, particularly if it isn't your first pregnancy and you therefore know what to expect. First-time mums often mistake those early flutters for wind (or that chocolate button craving they've indulged a little too enthusiastically).
17 weeks pregnant symptoms
We definitely had something to say about pregnancy symptoms in week 17… What was it? It’s on the tip of our, er… thingies… Hang on. We’ll go out of the room and come back in again. It might come back to us…
‘Preg head’
Feeling fuzzy-headed and forgetful? You’re not alone. It was long thought that 'pregnancy brain' was not a real phenomenon. However, recent research from Deakin University, published in the Medical Journal of Australia, found that there may be much more to it.